Honestly,
I think ut3 was pretty good in its raw form and feel, it was my favorite, with ut2003 being the close second, then ut following and only then ut2004 and then...
well i did like the uc mod for ut2004 so i'd probably like the game too but that's not "ut" in title.
And the last is UT4. It was on a good path during 2015 or so I felt and then it slid off to nothingness.
The only thing that could save it is...Mothafuckanation and king kong of the hill. (With Peter Jackson as an unlockable super player character and Michael Jackson if you start really sucking at the game and lose mothafuckanation)
oh yea and I like the ut3 pre alpha somewhat too. And UT beta for the maps because they were o-kay and more in style with original Unreal but the game wasn't that good until UT retail though it was still good when it was still expansion pack I guess...
EDIT: Oh and David Haselhoff hooga chaka player character too.