I think Jieb Chompoonuch looks too innocent to be n'rai.
But I think Benz Punayaporn looks very nang'ra-ish and she can pull that role of really good, she is one of my favorite young generation n'rai all the other young generation n'rais are stupid they cannot pull that n'rai role off. When benz first came into the entertainment biz I thought she looked too innocent to ever be n'rai and I never thought they'd let her be n'rai either but she's grown now and she looks more n'rai-ish than the innocent Benz I have known before but she is good as nang'ek too.
Here's a list of actresses that I think are good at playing the n'rai role:
Kik, Aom Skaojai, Noon Woranuch, Tangmo, Benz Punayaporn, Joy Rinlanee, Yui Jiranan, Ae Isariya, Bee Matika, Aum Pacharapa, Ploy Cherman, Noon Sinitra, Meji, May. F, and I think that's it might be more.
I wanna see Kob Suvanant in a n'rai role though, since I read an article long time ago that she wants to try something different other than being the nang'ek in her lakorns all the time.
I can never picture Pat, Namfon, Ann, Aom, Janie, Cherry, Kwan, Pancake, Poo, etc. as nang'rai in lakorns but they might be good you never know until they try out for the n'rai roles but I don't think they ever will the nang'eks that I see mostly as the n'rai is Ae Isariya, Benz Punayaporn, Joy Rinlanee and Noon Woranuch the most.