You will be much happier with a brooder plate than the light, and your chicks will, too. I find they feather out faster with the brooder plate and are quieter at night. If you hear a chick cheeping loudly at night under a brooder plate, it means there is something wrong - stuck somewhere or too far away from the heat plate and can't find it's way back in the dark. Usually they sleep quietly all night. They also learn to roost early because they will start sleeping on top of it.
How crowded it will be depends on the size of the feeder and waterer. If you are using the standard gravity flow plastic ones, it will be crowded and the chicks will make a mess because the chicks will constantly be IN the feed and water looking for room. I use small juice bottles with a nipple waterer that hangs for my brooder. The nipple system keeps things much drier and has a smaller footprint. I also have a rubbermaid container that sits on top of my EcoGlow with the nipple on the bottom at one end that hangs over the edge. That is great to start the chicks on because it keeps it right outside the brooder so they don't get cold going out to search for the water the first few days. Premier1 actually sells a similar waterer to use on top of a brooder plate. In a solid plastic brooder container like that, moisture is going to be your worst enemy, so anything you can do to keep the water from spilling will be a big help in keeping the chicks healthy.
You could also fashion a feeder from PVC pipe that would take up less room than the standard chick feeder.
A couple of tips - use either Glad Press n' Seal (cheaper) or removable shelf liner (more durable, but pricier) on top of the EcoGlow for easier cleaning once they decide to start jumping up on top. Also, I would flip the EcoGlow around so the cord is at the other end and protected from being jumped on all the time by the chicks. Learned that the hard way with the ducklings.
Good luck with your hatch!