The CDR and HP per lvl Rune stats should really cap out at level 10, 18 is way too far to be useful
90 / 18 = 5 HP per level
10 / 18 = 0.5 CDR per level
These two are quite honestly bad as they currently are, especially since you've done nothing to address the snowball in the game which pretty much always ends matches WAY before anyone hits 18 outside of fringe cases. Please just look into it, what could the harm possibly be in bumping the cap down to level 10 to make it actually useable?