China in MultiPlayer always wins, just keep producing Chu-Ko-Noobs. They can get Great Generals extremely fast with that two hit and Great Generals give an extra bonus to them thanks to their unique ability. If they go honor they're already getting that bonus as you only need one social policy after the opener to get it.
Then you have the Paper Maker which gives two GPT, a three GPT difference from the library which is one maintenance. If they get Great Libary, just quit, even if you have the Great wall, castles, it doesn't matter, they'll either GG your lands or mass spam those Chu-Ko-Noobs.
The Huns is very good for Horse Rush and sometimes they can get incredibly lucky and get a ruin with their warrior which will give it a Battering Ram, they can easily just snipe a capital with it, Cover I and 300% attack bonus? Seriously...? And that is a Spearmen replacement, anyone second city is dead because of this unit. You only need one of them in very early game. Horse Archers are also extremely OP and different to the Chariot Archer in every way possible. First off, the name, Horse Archer. HORSE. The Wheel? WTF? It should replace the Horsemen at Horseback Riding. It gets Accuracy I, extra range strength, extra defense strength, does not lose all of it's movement points in Rough Terrain like the Chariot Archer. And to top it all off? They start with Animal Husbandry AND their pastures get one extra production, they're a ridiculously overpowered civilization until the Renissance. Especially if they go down the Honor route. You can't compare nothing to The Huns in early game, any civilization is laughed at compared to them.