maybe that is why i tend to prefer them to farm, because i have never had a runner before my pop reaches 35. i don't restart games to get a better tribe. the only time i have restarted was when i wanted a hard tribe and i forgot to put it on hard before i started. i think. i could be wrong.
I don't restart to get a better tribe, but because I'm bored with my current one and want to start doing the puzzles again. Only times I've restarted otherwise were either because everyone died or there was a lack of females.