If you've got a queen ocean view room now, I wouldn't expect any upgrade. You're already ocean-view so the only thing they could upgrade would be to move you t oa higher floor.
You get the same gold benefits as any other Hilton (Wi-Fi, etc). No complimentary breaskfast because it is an all-inclusive. I think we got bottled water every day. There is also a discount on cabana rentals (10%?).
I would suggest booking restaurants (and cabanas now). Not only can you get better times, but the line in the lobby to book them is very long to wait in. We tried all of the restaurants. They were all OK and a nice change from the buffet style restaurant. I wouldn't expect to have your socks knocked off.
You can reserve a taxi/shuttle in advance or just pick one up at the airport. I think this thread has contact info for Greg somewhere. I can tell you that it probably would have been quicker for us to just get a taxi at the airport. The traffic at the airport was so bad that our driver couldn't get in pick to us up for some time.