My Crocs also rubbed on the top of my foot and kindof got red and sore too. But, after awhile, notsomuch. I wear new ones with socks to break them in, and I build up a tolerance for wearing them barefoot in the summer. (But, for WDW, I bring an alternate footwear just in case). I also do better in Beach vs. Cayman. there is a slight differnce in the fit, at least to me. I also love the Specialist (vent) ones in the winter, less drafty holes, and better for my jobs. (I have white for one (medical) job, black for the retail job!)
The trick to solve the "rubbing the top of foot" problem is to put the crocs in the dryer for a few minutes, and then when they come out and are warm, use your fingers to stretch that top part a bit. I also wear them with thick socks while they are warm to help stretch where needed on my foot. I have to do this for all my crocs and then there's no more top of foot rubbing!