If you do any canoeing you might also try St. Regis Canoe Outfitters at their Floodwood road base - it's on a portage into a motor free paddling/camping area. More or less rent and go:
The High Peaks is the "go to" spot because of the mountains and Lake Placid Village. OTOH the park is full of places to hike if you are not focused on climbing and crowds. There is a shelf full of books on hikes in the area. Ditto maps.
I assume you are going in the east side. If you do come out the SW corner through Old Forge and you will get a pretty good tour of the area. There is a lot more to the park than the high peaks. You can get maps and books at any of the gateway villages.