Before I start. But I usually only go for diplo, UN,tech or cultural. Domination is just tedious for me.
I've had games where I switched plans mid-game. But I play to Civ strengths, and it's reall fun exploring Sukhotai, and the Inca in particular. Two civs that are not really glamorous, but Inca is by far the most fun I've had in terms of really executing on a strategy.
Going from a few super mountain cities and parlaying into a massive empire mid-game was very satisfying - it's always nice when a plan like that comes together
With the Inca's, slowing that urge to sprawl and grab as much land/unique resource and instead cling to the mountains early was a challenge.
The AI and configuration of Civs, CS proximity account for 30-40% of my VC decision and diplomatic play as well. Some games are just rough.
And I'll freely admit 50% of my games I either exit for a better start or I get jumped in the early game with a bad alliance against me and I give up. All on the same difficulty. The variability in civ5 is quite high especially in the early game due to the differing intensity of competition depending on what AI I roll and where they are situated.
I always play with randomized AI. All DLC civs enabled.
My last 20 games or so are on Pangea / Pangea + for maximum diplomatic intrigue by the renaissance ; I avoid archipelago or any maps that artificially deflate difficulty.