[The Rider]

that means 3 or max 4 skill levels (from the cheaper ones) in addition. On impossible in my last replay I won 512 battles, that means 70 runes more (because you cannot take the iron fist/rune stone/high magic skills at early stage), 1/3 from each kind, enough so you can buy all the unnecessary but interesting skills, you couldnt afford earlier

Eddited:
I cleared all the Kordar area with that mod (loaded a previous save game), in 61 battles I got 7might, 5mind and 5magic runes, I got 3 levels in that time, started with 1 level of trophies and 2 levels of rune stone (10% chance for a rune), around the 32th battle I upgraded trophies to the 3d level and rune stone to the 3d level (so my chances were 20% for a rune). With 7,5,5 runes I upgraded only 1 skill and added 1 mind rune for another (I got the other runes from level ups and what I found on the map). So it is not overpowered. In fact I think that the game provides very limited choise of the skills you can take. The runes you find are not even enough to fully upgrade one skill tree, I remember that at the end of my first campaign I didnt have enough runes for the 3d level of high magic).