Improvement idea:

[RiverBummer]

It would be very useful to have a rune disintegration/dis-aggregation/break-down tool.
As we develop runes ever more powerful they become ever harder to be re-absorbed into other same tier pedigree runes. E.G. Who wants to make a Righteousness Level 6 (100% morale) a Level 7 (110% morale?) just so we can use up energy up from an old useless magic caster rune if we go to all physical fighters? Also as we get new gold tier hero cards some of our old rune sets are not the best combinations for the newer hero cards we acquire.

SOLUTION give us a new tool (e.g. a Rune-Tinkerer NPC) either in the Rune Screen or in a Magic Shop in Aerie City who we can pay a small 5 Gems (or credits etc.) fee to take any level purple or gold tiered rune to down-convert it into a packet/stack of generic-rune-energy tokens that can be re-absorbed by any other rune level green through gold within the Rune Temple.

This way we could use older high level purple & gold runes no longer effective for our newer formations to re-seed a whole new lineage/pedigree of runes from scratch but re-apply these higher level energy runes to lower tier runes we want to re-start.

I'd recommend that these new Generic-Rune-Energy Tokens be made to look graphically like runes but instead of adding attributes to the hero they are only combineable runes. Make them 20 stack-able in inventory and each one is a quantum of 1000 energy. You'd need two denominations - 1000 energy and 100 energy.

Or else give us a way to transmute Rune X into Rune Y at same level and class.

Would really really be useful.