riding the public park is a chill way to go instead of camps. You can get a ton of skiing in, theres lots of people who ride public instead of private camps, and camping down below is better than staying indoors.
The quality of the park does depend when you go. Earlier (like June) is pretty good because there is more snow, you can usually ski down to the bottom of the mile without hiking, the park is decent (with a superpipe, rails and boxes, and jumps and so on).
The public park is especially good after the ASJ (early-middish july). The jumps then could be upwards of 50ft or more, sometimes a good assortment of rails, and the pipe could be really good, too.
Skiing into August could still be decent, although by that time the park will most likely be in a canyon, and requires hiing, but hey, still really fun.
The weather is also far better at Hood in the summer than it is in Whistler.