Typical strategy game problem, once you got past mid game you can dominate in most of these games. In Civ 5 the end game on deity is not much different from lower difficulty settings. I guess the passive bonuses while changing the early game dramatically don't really impact the game as much by then. I believe the AI is more or less the same, it's just that they get more ressources to spend.
And in Civ 5 that means that usually you can choose how you want to win. Your ressources will usually suffice for multiple ways.
Diplomatic Victory is almost always a possibility (unless you have austria/venice in game). They never go all out to buy them up before a vote. I once had venice with 40k gold needing only 6 votes to win. He could have easily bought them. Its usually the safest way out of most games, its literally a gather about 20k gold and just buy the victory.
Cultural victory is not that hard to achieve. The problem is early tourism does nothing. You can go from 0 to 1000 tourism in a few rounds without ever having to do anything cultural before. Its actually better to delay the great musicians until you have the internet then pump out musicians and culture bomb them.
Science is ok, but can actually end up in a race. Nothing that can't be solved by 1-2 nukes on the capital city.
Domination is an endless grind of moving armies and waiting for happines to recover. The AI can be easily beaten by then.
Thats one of the biggest flaws in the game. The different win conditions are too close together. I usually find myself just taking the cheap way out and buy a diplomatic victory, since I know I would win every other victory in a few rounds anyway.
Its ok, but you pretty much have to rush 2-3 civs in the first 100 rounds. Otherwise your neighbors will declare war for space reasons at about medival times when they are the strongest in comparison to the players. The real pain of 22 civs comes from the engine, the load times in the later turns get atrocious.Another point about 22 civs, that's 10 more civs than a huge map is designed for, isn't that, I don't know, crowded as hell?