As an aside, the game must have been monumentally easy before that was patched. I am playing hard now and I haven't had too much trouble.
Not really. I used the feature, but the result was absolutely neglectable. E.g. on a glass canon mage a boost from 22 to 24 action points per turn. Or one more leadership level for another character allowing to exchange an armour 10 helmet against an armour 16. And more of that kind of stuff.
Simply insignificant, the battle difficulty is determined by fundamental mechanics and the player ability to focus his builds.