Well, there are mods made for Space Empires 4. I personally took one such mod and modified it to make the Milky Way look more like Star Trek. I play it from time to time:
However, due to the nature of the AI in that game, is quite hard to play UFP, as all the other players are prone to attacking you (even if they are not so prone to breaking treaties).
Each race can be customized up to what ships uses and even what tech is available to them.
I am currently playing on that map with a very large Terran Empire, which is close to conquering Romulans, Ferengi and is also at war with Dominion, Breen, Klingons, Cardassians and Borg. I also have Xindi, Vulcan, Son'a and Nausicaans as subjugated races. Betazed and Andorians were completely conquered.