Just a thought - I still get confused about what leader bonuses are active only if a leader is the commander of a stack. It would be nice to see what bonuses are active when you activate the stack tooltip.
However I can see a problem with this as you may have more than one stack in a region so it would have to also show for example what bonuses are active across stacks when besiging a structure with more than one stack (I think a few engineer type bonuses are cross stack). It's even more confusing when I'm trying to remember if a change was made to BoA in a patch or if a change has only been made to AACW.
Any tooltip help that could be made would be great. As I have mentioned before I have been 'studying' this game for a year now and some aspects are still fairly confusing - so it must be more so for newer players.
Cheers, Chris