Luan paneling doesn't have much strength, if there isn't something behind it, it can bow and break quite easily. You may want to consider something with more strength to it such as 5/8 inch OSB or plywood. Or you could hang drywall under the luan, and that would lend enough strength to avoid breakage.
As far as a finish, I'd use several coats of a high gloss polyurethane. Sand inbetween each coat with fine sandpaper and tack up the dust to get a smooth finish. The smoother the finish, the easier it is to clean.