Now this is just off the top of my head, but here goes.
First, Athena is probably as good an AI as I've seen in a war game.
That having been said:
A 'superior' AI might demonstrate the ability to conceptualize and carry out long term 'strategic' plans. (In my humble opinion, one of the great flaws of the Southern Command was that their 'long-term' strategy appears to have been 'stand on the defensive and beat the tar out of any Federal army that came south'. Whereas the Union decided on and carried out the 'Anaconda Plan almost from the beginning of the war, even in the face of reversals, and outright catastrophe, normally brought on by the seeming timidity of the Union Generals. All of the Confederate 'incursions' were typically for short-term limited objectives, the invasion of Maryland in 1862 was aimed at bringing Maryland into the Confederacy on the theory that they were a Southern sympathetic state suppressed by the Union. The invasion of Pennsylvania in 1863 was aimed at drawing off strength from the western campaign in an effort to relieve Vicksburg. Tactically brilliant, strategically meaningless.)
A 'superior' AI might have the ability to conceive strategies or tactics that maximize the strengths of the position and minimize their weaknesses. For example, the Union strategy in the actual war emphasized their naval superiority. It minimized the usage of cavalry til late in the war. Thus, their strength, in the form of a strong nucleus of a navy was matched against a confederate weakness, while a weakness in their cavalry, where, early in the war they were overmatched both in personnel and leadership was minimized.
A 'superior' AI might show an ability to perform better 'risk analysis', such as opting not to pursue with troops that had suffered severe attrition, when the situation into which it was pursuing was unknown. (This is a flaw I think Athena is guilty of sometimes. If I set a 'weak' unit, say a division, in a relatively exposed area and Athena defeats it, she will almost invariably pursue. Typically running right into the corps that that division just rejoined, which is typically flanked by two more with the army in reserve. Which often costs her an entire corps, if there's a cavalry division prepared to move in behind her. Or even worse, an entire cavalry corps. I've caught her with that three or four times.)
A 'superior' AI might show a better abililty gauge strategically important positions. Examples of this in Athena's case abound throughout the forum, as people talk about 'gamey' strategies pursued against Athena, mostly involving drawing her out with a diversionary attack on a strategically meaningless (relatively) objective and leaving Washington or Richmond wide open. Historically, one of the problems with Lee's two invasions was that they were obviously 'demonstrations only' as no serious observer would have believed any Confederate attack on Washington could succeed. After the debacle at first Bull Run, the Union defense of Washington was probably never less than a 100,000 men in multi-layered entrenchments, with the heaviest guns they could mount, inside brand spanking new 'modern' fortifications. Any assault on Washington which was not preceded by a campaign inflicting incredible attritional casualties on a Union Army that was 'in being' and stood some chance of surviving if reinforced speedily just wasn't going to succeed. However, Athena (and it might also be said, almost any AI in any game you care to name) can be convinced to draw troops out the Washington defenses in any number of cases. (For the historical purists, try creating the massive armies that Athena typically throws at the Confederacy and STILL keep a 100,000 man army with massive Artillery in Washington. This may be part of the answer to the questions about 'ahistorically large' armies by both sides. In all of the AAR's I've seen very little attention is paid to 'rear area security' and almost all of the action is crustal defense, rather than defense in depth, when in reality, both sides, but the Union moreso, held massive numbers of men in reserve, defending strategically important objectives.)
A 'superior' AI might learn from it's mistakes. Reading through the forum, it's apparent that some players have found 'gamey' strategies for defeating the AI, particularly when they are playing the south, due to some pecularities in the AI's assessment of threats. The one I'm thinking of is the one where they take advantage of the one region adjacent to Washington with no river barrier and no rail, which apparently reduces it's importance in Athena's decision tree. A 'superior' AI might fall for this once, but learn and not repeat the mistake. (One DISADVANTAGE of this might be an AI that learns might become 'unbeatable' over time. In which case, I'd suggest pulling the plug before we're all living in "The Forbin Project".

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Any improvement in these would represent a giant leap forward. Do I think these could be implemented? Not so much.

Of the bunch, perhaps the easiest to implement might be the one about improving defense of strategically 'important' places. This would probably revolve around increasing some 'value' already in the engine. Or a multiplier or somesuch. (Not knowing the algorithm used to determine 'strategic importance handicaps me in knowing how 'easy' it might be. I'm just blue-skying on this one.) The others, well, if y'all were good enough to program that in, we'd be reading articles by you in all the technical journals after you'd collected your Nobel Prizes for creating a true Artificial Intelligence.

(And probably reading articles published by Athena as well. Right after she cured cancer, solved the problems in the Middle East, and came up with a faster-than-light drive.

) The point being (now that I've got my tongue out of my cheek) is that I suspect it's a lot harder than it might seem.
Now as to why I think Athena
is a "superior AI", at least in comparison to most of the ones I've seen:
Most of the time Athena at least seems to be TRYING to think strategically. She can sometimes be 'diverted', the strategy may not be the best one possible, it may not take advantage of her sides strengths. But at least she's trying. Most of the AI's I've seen have no concept of the difference between 'tactical' success and 'strategic' success.
Athena's behaviour can be 'optimized'. If I think that reducing the fog of war for her causes her to be too aggressive in 'pursuit', for example, I can mitigate that to some extent in the next game by adjusting a setting and reducing her ability to 'penetrate' the fog. I can force her to live with the 'historical' traits of her generals, more or less, by adjusting the activation bonus. Generally speaking, there is more ability to 'fine tune' the AI than I've seen in any other game engine. If there's any 'drawback' to this, it's that you have to play a few games in order to get a 'feel' for what a particular adjustment will do, AND how it may interact with the other optimizations.
The AI WILL react differently in different situations. What I mean here is that if my strategy changes, so does Athena's. I normally play the South. And I generally play a fairly 'defensive' game the first year, while I organize my forces, trusting that even if Athena manages to get McDowell or McClellan to move, they'll just be coming south without trained troops, with low cohesion, and inadequate coordination. All of that being 'inherent' for both sides early in the war. And the defensive being stronger than the offense. Even so, there are 'variations' within that. For example, I might build up a strong cavalry division under McCulloch in Texas and embark on the 'grand tour' of the western territories. If I start by taking Tucson, (almost a must for this scenario to have any chance of success), then Athena WILL react to that. (If I start by going for Denver, she reacts, but late, and not the same way.) Same if I force action in the Tennesse/Kentucky theatre. If I don't force action there, Athena has a pretty standard sequence of actions, but they vary sufficiently that they aren't 'predictable' in the sense that she may always attack Lexington, but not necessarily always in the same force, and what she does thereafter is subject to change, based on what, I'm unable to determine.
This has been an interesting exercise, but when it comes right down to it, my feeling is that while it would probably be possible to 'tweak' the AI in a couple of places, with varying degrees of difficulty, I doubt that it could be improved a whole lot. The suggestions I had for a 'superior AI', if they could be implemented, would likely make the game engine far more valuable, as I could get you a REALLY good contract with the Pentagon. I suspect that Athena's ability to think 'strategically' is probably as good as it gets. Simply because the number of variables is way too high for straight computation to achieve an answer in a reasonable time. (If you were to decide to write one for a heuristic 'neural network' type computer, it would probably be a LOT easier. Of course, I suspect that the potential market might be a bit limited. Actually a LOT limited.

Same with 'learning from mistakes'.
It might be possible to improve her 'risk assessment' but adjustment of the 'fog of war' seems to work almost as well, once you figure out what that affects and adjust those parameters as well. (I find, no fog of war reduction, normal aggressiveness, some activation bonus, works pretty well, although it can be interesting to change one or more of these just to see how it works out, even if not 'optimal'.)
Improving the 'survival instinct' in defending important objectives might be doable, but if were me coding it, I'd want to do some extensive testing to see what kinds of alterations this made in her behaviour. (Might cause her to be so cautious that it wouldn't MATTER if McDowell ever activated, she wouldn't have given him a large enough field force to do anything with.

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There's my two cents worth. (Actually more like $1.95. Which, if converted to Euros would probably look like two cents again.

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