I runecraft quite a bit so here are some GP/Hr you can expect if you're using stamina potions, weigh reduction gear, and play legit:
44 - 50: 350k/hr
50 - 75: 450k/hr
75 - 91: 600k/hr
91 - 99: 1.2m/hr
Note: I have 99 runecraft and while runecrafting I'm usually watching TV so your results may be different from mine :P