Well for me it depends on where I am in the game. Obviously Cloud, then Barret is second, Tifa 3rd. (I prefer Tifa next to me though so she's second spot.) Then once Red is obtained he replaces Barret. (Aerith and Cait can kma cause I like to hit hard they no hit hard :O) Then once I get to Nibelheim I level up until I can defeat Lost Number and obtain Vincent, then he replaces Red and that's my party for the rest of the game. Until you lose Cloud, then it's Tifa Vincent Red. Then once Tifa leaves Cid replaces her the others stay the same. Then once Cloud is reobtained back to Cloud Tifa Vincent ^.^