GLC that's a good point regarding thinness and flautas, and I agree. I think that applies to taquitos too. I've just recently posted a taquitos recipe in DC's ethnic food section, and when I cook that I like to use two partially overlapping them to get increased length. (Actually I'm not sure what the technical difference is between flautas and taquitos.) Anyway I used Mission yellow corn tortillas which the manufacturer claims are thinner than usual commercial tortillas. I may be putting too much into it but I've assumed their yellow corn tortillas are thinner than their ordinary corn tortillas. Anyway the Mission yellows worked well even when overlapping.
I'm a real chiles rellenos lover too! I like to make my own and I'm really pleased with how they come out, although they are often pretty messy in my kitchen. Maybe I'm skillful or maybe I'm lucky, or maybe chiles rellenos are just good when cooked at home from basic ingredients. I vary my recipe a lot which prevents me from posting my version(s).
ETA: Was just musing... Q: What do you call just one chili relleno? (A: Not enough!!!)