Invuln Axe.
The only thing you have to sort of pay attention to is Dull Pain, and I only use that in really tough fights. Set Brawl to autofire and your chain becomes:
Beheader-Brawl-Chop-Brawl-Beheader-Brawl-Gash-Brawl. Default recharges line up exactly, and the end use is manageable. The time it takes most foes to stand back up is the time between the attacks which all have a change to knockdown. I've had fights where the boss I was fighting never stayed upright long enough to attack more than a few times. You can start using it by level 4 and it's really all you need until the 30's.
Carnies will be unpleasant and anything Crey tanks will take a long time to kill due to lethal resists, but it's about as simple as they come.
Willpower is the other choice for maintenance free tanking. The only thing to deal with there is the Tier 9 click power and that's right before a really big fight or when things turn ugly. Because of the additional recovery, you don't need to slot end reducers into toggles. You can slot the entire powerset with 16 slots making it very open to slot your attacks. Ranged foes will tear you up a bit, so Nemesis are a danger. For some reason, every WP character I have get torn up by Dev Earth as well.
