1. MSCC - Kublai Khan of Babylon
Cre/Cha. Bowman/Garden (now a Granary replacement)
Gets the 70% bonus on Libraries, but I still don't see Charismatic being better than a pure eco trait in isolation. And Babylon just seems underpowered, maybe I'm wrong but I don't think getting Granaries at Agri will make any difference at all, and the 15 saved hammers aren't hugely impactfu. The Bowman is largely irrelevant, especially since they got to pick their Civ after everyone else and no-one picked any ancient/classical era rushing units. If I were in their shoes I'd have picked a civ with a more useful UU to go along with the CHA trait.
Wheel/Agri - Not as good as Mining/Agri, but still, could be worse.
2. naufragar and Rusten - Alexander of Japan
Agg/Phi. Samurai/Nanban Harbour (a Harbour that gives +2 xp to land units).
I was looking at Japan myself, but why they didn't pair it with an Expansive leader is beyond me. I suspect they'll find themselves not building that UB as much as they think they might be thinking, 80 hammers is a lot. Also, pairing PHI with a non-eco trait like AGG (-25% city maintenance doesn't really count) seems like a poor decision, I played PHI/CRE a few games ago and I didn't like it much at all. If I picked Japan I would have gone with Washington as leader. EXP for the cheaper UB (and other bonuses it gives) and CHA to better take advantage of all that xp. Samurai are just kinda meh. Maces always seem to have a really short period of usefulness. Too expensive to be whipped en masse and quickly overshadowed by Knights on offense, and the Samurai isn't so good that you build them anyway (unlike the CKN)
Fishing/Wheel - poor starting techs, even with seafood. Having to leave BW to the third or even fourth tech researched just feels bad man.
3. boak and GeneralKillCavalry - Bismark of Vikings
EXP/IND. Berserker/Trading Post (Lighthouse with half a dockyard attached)
Vikings will be good on a water map obviously. Bismark I'm not so sure about, but being the only IND civ is still good. I expect an early attempt at the Pyramids and/or GLH. Or a plan that involves the Oracle. Solid combo, although the Berserker has the same problem as the Samurai, but is slightly better on a watery map.
Fishing/Hunting - decent starting techs for a WB first start only.
4. superdeath - Sury of Korea
EXP/CRE. Hwacha (now can kill units)/Seowon
I was looking at Korea when making my selection but decided the CKN to be the better collateral unit, but in most other respects Korea is the same as China, although the UB is better if we get that far. I'm interested to see how the Hwacha does. Sury is still a great leader. This looks like a combo picked with the same thought processes as my own so I have no criticisms
Mining/Agri - Still the best starting techs.
5. Borsche - Mehmed of Carthage
EXP/ORG. Numidian Cav (HA with bonus vs. non-spear melee units)/Cothon (Harbour with +1 TR)
Another power leader like Willem or Sury. I don't know if ORG will be as good on a small map, but this combo will save an awful lot of hammers on all the buildings it gives production bonuses to. Carthage looks pretty good, the NC is gonna be the same as a HA on the offense, but better than than the HA at killing invading stacks. The Cothon is just a better Harbour, and will actually get built with an EXP leader.
Fishing/Mining - Good if there's a three-hammer tile and seafood by the cap, otherwise fairly slow.
Me - Willem of China
Creative is still in the top tier of traits. It's hard to quantify the difference free border pops makes, but I can really tell the difference without them. It makes city development and dot-mapping so much easier.
China is also still good. Best starting techs and a top tier UU. I definitively want to be on the offensive once CKNs start to appear.
Overall, there are some good combos here and some I don't understand. But the only way to really know is to play the game.