If you have multiple requests, I suggest you call in advance so you can "prioritize" them. For example, you want first floor room near the bus. What may be available is first floor far from the bus, or second floor close to the bus. You'll need to decide what is most important if not all requests can be met, or WDW will randomly choose which one to give you. Also, keep in mind that some "requests" are actually bookable categories at certain resorts and unless you pay additional for that category you are not likely to have the request granted.
Enjoy your vacation!