Raise up your waterer to help with the shavings issue. We just use some wood cut offs to raise it with “steps” so they can access it. Plus, if it’s on a larger piece of wood, fewer shavings nearby. So, use what is convenient. Or buy something inexpensive but easy (paver, thin cinderblock type at home store). We also had an issue with larger chicks knocking over the feeder (the chick type with taller plastic screw on container, colored bottom with holes), so we screwed the base to a square piece of plywood, problem solved.
We used vertical nipples with one batch of chicks- they were awesome ….until they weren’t. One started to leak and would completely empty into the brooder. It seemed like maybe some debris got in, but try as we might, we couldn’t fix the leak. It was annoying to have purchased an item and it stopped working with one batch of chicks!
Regular horizontal nipples would be too hard to use for very young chicks.
Only other comment is that we use waterers with the open trays for all ages. We’ve tried horizontal nipples for adults. While they “got it” and used them, seemed water consumption was less than with more open waterers. But, they are very nice for keeping out debris. So, we have our run waterers raised up on solid cinder blocks, or hanging at back height.