Sterak's Gage - An Idea Toss Up

Would it be possible to alter the value of maximum health-based shield instead to some value of bonus health-based shield instead? Fighters and tanks invest in bonus health, something marksman squishies are just not ever going to build (outside of maybe a Frozen Mallet), so it wouldn't necessitate it being restricted to ranged or melee.

This is just something I thought up, I'm sure my idea has just as many if not more so flaws than merits, but I'd like to discuss those flaws as well as merits.