Just thinking about the top ten things I'd like to see off the top of my head. SOme may be on their way, but I thought I'd throw it out there anyway...
Increased Map variations – Arctic, desert etc. up to the number of XCom ones
Enhanced Geoscape events, in parallel with UFO activity, showing the panic, or cooperation, within the funding nations as the invasion progresses.
Training to be enhanced to ensure that you don’t spend the last third of the game with cookie cutter soldiers.
Variation between funding nations – with geography, expertise and cold war influence affecting various facilities, buying & selling
A more detailed Geoscape with more cities on it.
Female soldiers, if only in the base pictures – coming with $200 000 I see
Enhanced solder screen enabling room for call signs, character roles, and possibly player notes.
Enhanced alien artefacts – more to their culture/goodies than just power sources and alloys. Can be looped into research
Being able to track alien influence on funding nations – colours on Geoscape or enhanced funding nation info
Remove soldier from selection and force onto next soldier when going through soldiers on Battlescape
Oh, and to help for post release...
Mod – Ticker & events to be moddable
Mod – Psionics to be moddable preferably with a graphic of a Psi Amp & Psi Lab to be handy
Mod – weapon effects to be added beyond what is there – electrical arcing for example?
Alas tech, pilot and engineering skills are probably huge, but enhanced training would almost be the same as Soldier skills.
What would make everyone else's list?