Your boots sound about right, they should be snug without the toes curling, and your toes should just brush the front standing up, and pull back slightly once you're in a riding position, i.e. with the knees slightly bent. My toes are still ever so slightly jammed against the front while riding, but that's personal preference.
Heat molding will help a bit, but it's mostly about going out and riding and the boots will break in a bit. I'd go with thinner socks, even barefoot for the first day or so until they pack out.