I stick with my phony ponytails (on top of my head), so as not to stretch (with the possibility of breaking) my nape area. any flyaways or loose strands i have in the back i just use some fantasia ic gel or some sort of moisturizer on it and let them curl up.
i'm looking to start rollersetting my hair more often (i purchased macherie's dvd and hopefully it will help with my technique).
you can also try flexi rods (that's my next step if this rollersetting does not improve lol).
braid outs are good (if you can braid, cuz i know i cant!); i too tried flat twists, but i can never get the parts straight and the back is always loose!
hopefully other ladies will chime in.