I've done the loop a few times. You're in for a real treat!
As for waterfalls at the campground, you may find a few, since the Wooden Valley campground is right on a small river. I haven't explored much in either direction though, but it runs swift and it's sound will no doubt lull you into a restful sleep.
Springs are pretty unreliable, in my experiences. But a good place to camp is at the col between Cornell and Slide, and you can find water near here. Several designated spots along here, all of them primitive (no outhouses).. and excellent spots. If you camp there and the springs are dry, you can bushwack down to the Neversink River. One time a couple of years ago, we went in the middle of a looooooong drought. All the springs were bone dry. We bushwacked down and found the empty river bed near the beginning of the Neversink. We went down about 1/2 mile from the trail, and found trickling water that was suitable for filtering. Of course, exercise much caution when bushwacking down the face, Map and compass skills are a good thing to have if you're going to do it.
As for the steeper sections.. yes there are a few tricky scrambles. If you don't feel comfortable with any of them, just have some rope handy.. take your pack off, climb up, and then haul your pack up. That'll make it easier.
Best of luck, and have a great time! Though I'm sure you will.