If you could take a UA, UB and UU from any three civs to make your new favorite OP civ which would you choose?
I would take:
UA: Phoenician Heritage (Carthage)
UB: Jelling Stones (Denmark)
UU: Pictish Warrior (Celts)
I think this would give me the most insane start imaginable, and between the fast religion and jelling stones continue to speed up my snowball all game long.
What ideas do you guys have?
Well, I doubt anything can beat your civ in OPness, it even starts with enough culture to get the first policy (unless it was removed, there's a 25 Culture burst after a Jelling is built, scaling with game length) and has +2C base on top of fifty billion gold from Carthage and free city connections. The only thing arguable is the Pict as there are arguably better UUs like Conquistador, but is it worth trading early Faith and nearly guaranteed religion for? Depends, you should get so much +Production +Culture +Gold from your combination that religion should be doable at all difficulties, simply spam cities and build Shrines asap, but it'd definitely not be as easy. That's trading early strength and early convenience for arguably higher later gain (UU that kills everything + super-pioneer cities, even if free Mission is replaced with a regular Castle).
I'm going to instead say what would be fun to see:
Zulu/Swedish UA
Dojo
Samurai
A Samurai with Sincerity with Zulu UA... The speed of this guy levelling up would be unholy. If that Samurai then got another bushido promo, it'd be lots of fun. Swedish UA instead would also be enjoyable but the XP gain wouldn't matter at all as 10 XP per GG is what a regular Sincerai gets for hitting someone once so it's nothing compared to the might of less XP needed for promotions, but having way more +CS% than Zulu in the UA would mean the Samurai would eat everything in his path with incredible ease, but at the cost of maintenance money/tribute gains.
The worst civ would probably be:
Danish UA
Coffee House (I disregard tile-dependent UI/UBs on maps with little to no of that tile because yeah, they'd be worse)
Any ultra-late UU
Coffee House has only the +GP% rate pretty much from what I remember, the Culture>Science (or was it the opposite?) is not worth much. UU (Panzer) is too late to make an impact for a civ that's got almost nothing special for the earlier eras.