I think that there already alot of ambitious projects on this forum, its better, as been said by Icemania, to cooperate and improve
There are few that are going on:
Icemanias AI mod - well thats its massive improvement to ai performance and some balance in game
Unforeseen/Lurchi research on research - very ambitious projects on overhauling tech tree
My project of Alien Immersion/Beyound Universe in collaboration with Ergie - which focuses on even more variety/customisation , immersion, original per chararcter art, racial ship names, alot of design and variety.
All this on base of Haree78 extended mod with Das Chrome.
All of those combined = my dream mod.
I personally not interested in total conversions (like WH/Star Trek), i just dream about game that have immersive gameplay, huge variety and flavor of different races and approaches, huge replayability , depth. If you like it you can join to any of those with your ideas /help. All they are very ambitions and will surely benefit from some new creative ideas.