28's on the strand will be fine, even 25's are OK. if there's a lot of drift on the path, it's going to be "slippy" regardless, you just have to watch for it and ride carefully through it. focus on finding a bike you really like from a shop that your really like that's convenient to where you live. commuters generally have some kind of bag (knapsack or the like). make sure you're happy on your bike with whatever light cargo you're going carry. buy a bike you truly believe will be "the one" for years to come. don't sweat the tires too much.