Having flown on both, I find the CRJs to be much more cramped for seat and height space. The seats seem to be narrower than mainline, and my knees touch the seat in front of me (I'm 5'-8"). I find that I have more space on AT's 717s than DLs 767-400s for pitch. I would say the space on a 717 is the same as DL's MD-88s, one of DL's older planes, therefore, not as cramped a configuration as their 777s or 764s.