Watch it be something totally out of the box, e.g. similar to no stats on armor, weapons dont have dps only abilities(hamstring, fire arrow), and then mobs wont have hp only a 'hit count' say 10 hits kills a kobold and 50 on an orc and so-on.
That way, even when you are tier5 you could still be overrun solo by 10 kobolds, but maybe your tier5 mace has some abilities to help mitigate crowds.
Edit: And it falls into the 'as long as a healer helps do dmg' (attacks) they'll be participating, and cuts down on gear/dps inflation. And maybe certain affects, like fire, count as 2 hits vs a mob w/ fire weakness.