Yes, you can make reservations at the spas as soon as you board.
You can make reservations at the alternative restaurants whenever somebody is there to take them, which practically is most of the day. I'm hearing rumors that the fee for the alternative restaurants recently jumped from $3.50 (which basically was a tip for the server) to $15 or $20 -- which we all ought to boycott since the cruise fare is supposed to be all-inclusive.
If you wish to eat at the alternative restaurants, I highly recommend doing so for lunch rather than for dinner so you won't miss dinner in the dining room. In my experience (six cruises with Princess, including a twelve-day cruise aboard MV Grand Princess in the Mediterranean), the food in the main dining room is very, very good and, with a different menu each night, not exactly lacking in variety. The service in the main dining rooms is consistently outstanding, and the waitstaff have a great sense of humor.
Thanks, Norm. I will certainly be boycotting Sabatini's and the ice cream. The main dining room is one of the highlights of our cruising experience so I'll try to make reservations for the southwestern restaurant for lunch shortly after we board. I'll try to get a massage scheduled as well. Maybe send the wife to the spa and me for lunch reservations.
Be sure to verify the amount of the charge before making reservations at The Painted Desert. I'm sure that they put on a great lunch, but not one that's worth a surcharge of $15 to $20 per person!
BTW, Poseidon's Pizza (port side) and the Trident Grill (starboard side, both located immediately forward of the main pool area on the Lido Deck, are excellent lunch spots -- and both are included in your cruise fare!
I've been told Sabatini's has been upgraded to a very deluxe Italian restaurant, comprable to the Olympic on Millenium in quality. Personally when I sail Grand again I won't boycott. And I like the ice cream bar and although I shouldn't, I indulge myself there too. No negatives while cruising. It's too much fun. My favorite alternative restaurant onboard Grand or any Princess ship for that matter is the Bistro. In the evening after 7:30PM the Horizon Court buffet becomes a sitdown full menu restaurant. I've never seen more than 20 people or so eating there at one time and the food is most definitely cooked to order and much better than what you get in the dining room. I always take a few dollars to tip the servers because they richly deserve it. On the Sun class ships, there is even music for dancing in the Bistro.