%health runes should be buffed
If you rack the quints and seals for %health they equl +9% max health.
At lv 1 with like 600 hp that equals 54. So you would start off with about 2/3 of what you'd get with only flat health seals, which would leave quints open for whatever. Of course it would scale better into the late game, but it is definitely nothing much.
with 3000 hp you'd get a bonus 270 HP. You could have just went hp/lv seals for the 216 health at lv 18 and you'd have your quints open for whatever.
I think the %health runes could use a buff. No one ever uses them for a reason, they are far too weak. I realized this messing with runes for a support page (nautilus).
I think boosting seals from 0.5% -> 0.75% and quints from 1.5% -> 2.25% would still be healthy, and definitely add a reason to consider using the runes. That would total it to 13.5% from 9%.
That means at lv 1 with 600 hp you'd get a bonus of 81 health. slightly over what you would get with flat health seals. However lets not forget you are also using your quints here. So it balances out.
with 3000 hp you'd get a bonus of 405 hp. If you are going for a very high HP build like 4000 hp that'd get you a bonus 540 hp. Even then, especially for supports it'd be a tough choice to sacrifice 4*3=12 armor from quints alone for 6.75% max health boost. It is a weaker start.
I just think we have some runes in the shadow of the more mainstream stuff.