Quote from ChA1NsAwAge of Empires IV (AoE2 gameplay)
So much this. I'd like them to re-cover the eight ages done in AoE and AoE II. Later eras just don't suit the gameplay IMO.
I'd also like Quake 1.5 (i.e. shamblers, knights, lightning-gun-discharge etc.) and Ecstatica III.
Edit: Oh and Day of the Tentacle II and Dark Forces III (going back to a good mix of guns and sabers, as opposed to the sword-fest of the ID-Tech 3 ones).