Ever since the introduction of damage over time spells (dots) casters have become better than melees at: self healing, trash clearing, boss dps.
Dev's you obviously don't seem to understand, but this game sucks for melee now, they're irrelevant. Bodies there to suck up some sp, whilst occasionally getting to deal with a casters left overs. It started when vorpal was changed to it's current implementation, whilst simultaneously allowing insta kill spells in epics.
The game dynamic shifted from a mass hold / disco ball beatdown, to sitting back letting casters kill trash, when melee came in to dps down bosses.
With the introduction of the following spells
Eladar's Electric Surge
Niac's Biting Cold
Divine Punishment
You then pushed casters further ahead, giving casters sustainable dps that is on par / surpassing melee dps output.
These spells have no save, are cheap and very high damage. They're over powered. They have been since they were introduced as a no save, cheap, stacking spell.
You now have a tool to help balance this, consider adding these 3 spells to the list of spells with a reduced bonus from spell power.
This is not the path I wanted to go down in terms of seeking balance, but given your recent nerfs, it's obvious you can't / wont buff melee to be more fun / viable. So rather than buff melee to help them reach casters, I ask you to please consider nerfing casters down to the level of melee.