I think Florida is the only 1 seed absolutely guaranteed to make it past the first weekend.
Gonzaga presents problems for Arizona just in the way they play. The experience of the team and coach could cause problems. If Oklahoma St makes it past Gonzaga (they might since they'll have the best player on the floor), Marcus Smart will again be the best player on the court, even though I really like Gordon from Arizona too.
Virginia is a tenuous #1 seed. They got it by default. Memphis could really bother them. GW wouldn't give them nearly as good of a game. I'd say they are the 2nd safest #1 seed to make it to the 2nd week.
Wichita State will not have the best player on the court regardless of which team they face in their 2nd game. Randle at UK is a beast and Marcus Foster at KSU is simply one of the most underrated players in the nation. UK might be the dumbest team in the nation with some of their on court play, but still dangerous.
If they all do make the 2nd week, I don't see Florida even being challenged until the play Kansas. Wiggins is the best player in the college game and could keep it close. So I seem them easily to the Elite 8.
Michigan State will probably beat Virginia. That's the 2nd Thursday.
If Arizona get's past the first week (likely), the only challenge will come from Wisconsin, and that's only due to style of play. Arizona and Florida are both likely final 4 bound without too much issue.
If Wichita State plays Louisville here on Friday, that will be the game of the tournament. Saint Louis will give the Cardinals a game the week before, but will probably prevail. Winner of Wichita/Louisville goes to the final four from the Midwest. Toss up.
I think it's possible UVA and Wichita both lose in the sweet 16. Since UVA will be playing on the Thursday, they'll technically be the first 1 seed to fall.