So first of all, Harvard offers SINGLE-CHOICE early action only, which does not let you apply Early Decision anywhere and limits the schools to which you can apply Early Action. MIT and CWRU both offer non-restrictive early action, which means you can apply to both and even if you get in, the decision is not binding, unlike early decision.
IMO, applying ED just b/c you want to go to a selective school is not a good reason. You should only be applying ED if you can afford the school, but more importantly, LOVE it, as you’ll be spending the next four years of your life here. It seems from your post (correct me if I’m wrong,) that while you like CWRU, it’s not your dream school, and that’s fine: apply EA or RD and widely to other schools as well (safeties/matches) and wait and see what happens, rather than feeling in the future like you “settled” for a school that wasn’t your top choice.
Hope that helps! Good luck with admissions!