Thufir recommended Scarlet Heroes, and I heartily recommend it. I cannot speak about RuneQuest as I never played it, but Eclipse Phase is a rather rules-heavy game to get into, whereas Scarlet Heroes is based upon Basic Dungeons & Dragons which is a rather minimalist and rules-lite game.
The best part about Scarlet Heroes is that it implements rules so that a one-person adventuring party can still kick ass and not get overwhelmed in dungeon crawls. It handles this by tweaking the hit point and damage system a bit for your hero's staying power while making monsters easier to kill; a Fray Dice which represents short quick attacks so you can hit multiple weak opponents at once; and a "dodging doom" system where you can wager hit points to avoid a certain death effect.
Regarding not doing the same thing over, there tends to be a lack of options at low level, especially if you're not a spellcaster, but it has an open-ended skill system and you can multi-class to become a fighter/mage or what have you.
I've played quite a few Scarlet Heroes games with my normal gaming circle, and it does hold up well system-wise.