I have 7 currently, so 8 total characters. I have my main character (who was not my first character to create but became my main solo character) that I do everything on. But I would never fantasia her. She has a set look and personality. So I have alts to try different races, to redo MSQ at that newbie level instead of through NG+ (though all mine predate NG+), to play with my hubby who doesn't play nearly as much so I keep someone where he is at MSQ, to go all through crafting again because it's fun, because I always had alts in other MMOs so it feels weird not to have them, and before the amaro I only had certain classes on my main so they were a way to experience those other classes that fit them RP wise. I've since come up with an RP reason for my main to be a jack of all trades (and discovered how much I really love some classes I had ignored) but I still tend to let my alts specialize in their given professions.

When I start an alt, I give the alt some seed money to start with but then also challenge myself to test what tricks I've learned over the years for gaining gil and building that alt up. I'm thinking when the new NA servers go online, I may go make an alt over there and start completely fresh and meander my way through the MSQ like an almost total newbie (can't erase my knowledge of dungeons) just for something a little different to do from time to time.