What changes, if any, would you like to see in the gameplay in AOE4?

Many of you have played birth Aoe2 and Aoe3. Are there things that you hope Aoe4 will have that are different to either of these games? Are there things that Aoe3 did better than Aoe2 that you hope continues into Aoe4 in some way, and vice versa?

I still play 2 more than 3. I would personally like to see the ability to queue up units once you've reached max population; we see this in Aoe2 but not Aoe3.