I dont think party points even come close to a 33% rakeback programme or similar.

If you tilt easily or don't fancy extremely high levels of variance then play NL... If you really want to get a rock solid understanding of the mathematics of poker then play limit. I also think limit is an easier game to play whilst developing your multi-tabling skills if you ever plan on 6-tabling etc.

FWIW - I play 6max limit cash games for the grind, and NL mtts for fun (and to stop my NL game from going "rusty").