Just been playing a quick game with v9. So far everything seems fine. Even the scroll bar is back in the tech tree. Few turns to get to chem yet , so unsure if I will be able to go further. Guessing it wil be fine tho, nothing looks out of place or requiring 2 of the same tech in the civilopidia thingy.
The AI seems to make use of the 5 units in a stack thing...mainly for moving tho, once it gets in your borders and begins the fighting it splits units up, taking positions so to speak. I did see them use a spear unit in same tile as seige a few times when I had a few units around near them...so perhaps the AI see's the need to protect the seige unit and makes use of the fact it can move a strong melee unit in with it?
Not sure if i just have missed a hot key for it, but you cant tell what is actualy in the stack....or theirs, this ofc doesnt realy make much difference. I guess you attack with the strongest unit, and defend with the best.
To be honest I was kinda doing the same thing as the AI when it came to it, made use of the stack movment, but then split them up a little making a frount when attcking.
Also, when you are at peace, it feels more like you have a standing army, rarther than units scattered around for no reason. So yes, I'd say the 5 unit stack works realy well. I wouldnt go higher tho i dont think
Anyway, will post how past chem goes. Good work sir