I agree with you and have the same questions. I thought Snow would show up in more timelines but he was just in the one. (SPOILER)He wasn't even in the ending at all! Was Serah just going to happliy go live in 500AF without him? If you read some of the Fragment logs you do learn more about his journey but it's mostly lame and doesn't really settle anything. The gaps in this story are cavernous and Snow's most of all (actually Sazh is worse (SPOILER)WTF how did you randomly get to 500AF with your boy all of a sudden?). Also, Serah doesn't seem to care as much about him as she does Lightning. I love my brothers and all, but if both them and my fiance were missing my search would be for her first, sorry bros. I never liked the two of them as a couple and the treatment of their relationship in this game was just plain awful.

The only cool thing about Snow was that he joined you as a guest in that world, giving you a 4-man party for the first time in FF in ages.