Suggestion for early game Runes? Can you change Relentless Hunter to Ravenous in the Calamity page?

Currently every option aside from the Mage/Caster page has a form of HP sustain that allows people to stick around in lane longer and remain healthy in prolonged fights.

Calamity however does not and instead of providing the Hunter option that gives incredibly helpful lane-sustaining Spell-vamp new players get shafted with Relentless-Hunter which gives an underwhelming 8/16/24/32/40/48 >>>Out-of-Combat<<< MS.