Hello! I saw a sugestion about more interactive battles and read through it and I also think that battles right now are pretty boring. However I think the battles should be more tactical which will bring with it the interactivness.
My vision of how battle should function is the following:
Right now we have gems that are used for spells. Why not make each weapon come with different attack and defense moves that will depend on the skill of the player?
Basicly lets say you buy a sword. Swords will have different attack moves with different damages and defense gains/loses. Say you have just 5 slashing skill so you can unlock/use 2 basic attack moves and 1 defense move.
This moves will be represented just as the gems and you should put them in a separate punch so while in battle you will be able getting 2 different kind of "gems" - the weapon ones and the spell ones. You then should decide how to combine them depending on the monster you are fighing. This leads me to the another important topic: monsters AI.
For this system to function monsters also should be able to use different attacks and defense moves and why not spells? This should be quite random so the player will never know if the monster will cast a spell on him or maybe it will defend- so he will have to carefully choose what gem to use. If he uses a phisical attack gem but the monster choses to defend he will have lost precios energy without doing any damage. I hope you are getting my idea

In this way the player will be actually controlling the battle and not be just a passive observer.