You can't judge how roomy the bike will be by the specs, FWIW.
The CR is a small feeling bike.. Low and long.
The YZ feels low and short.
I ride a '00 KX250, I'm 6'5 and it feels the roomiest to me. Very nice riding position.. I wouldn't recommend buying one though, Kawasakis are junk and this is my last one ever.
The RM has a different feel altogether. It's a love it or hate it feeling, IMHO.
I haven't ridden a KTM, so I won't comment, but from what I hear they are the roomiest and best suited to tall riders.