It's still possible to retire the pioneer unit when playing as an Empire faction, as we can no longer build units with pioneer packs this puts an immediate end the the game!!
KruzChuk
I like the idea of using resources to create other resources. I think it could add a lot of depth into the game, especially if it creates new professions/buildings which in turn help to make more specialised cities. This could also affect the production rates and strength of weapons, amour, buildings, etc.
I love the customizable unit aspect of the game, but I'd like to see it improved. I think sovereigns, champions and even later game units should have access to special abilities and traits (elemental attacks, rage, round attack, multi-shot, etc.) that can be gained either through experience or magical items. I also would like to see the Dynasty and Diplomacy Systems improved to give the game more depth.