Just looking for some feedback on what are the better armor enhancements to aim for based on a frequently soloing melee character.

I'm finding invulnerability has helped my life expectancy considerably in the 6-10 level range; is there a point at which it becomes obsolete?

Also; Fearsome or Deathblock? Both would be nice but that doesn't seem to drop.

Any other enhancements I should keep an eye out for?