I tried it myself, I've changed the gold and the experience more (for the experience it seems to be useless because the monsters adapt to the level with each change of world), but impossible for the characteristic points or the skills (it's +10 max for all not above)
So after a few tests in the configuration files, I found "balance. txt".
in it you will be able to modify a large part of the game to make it more insane, for heros with at attribution points see for the file "gameplay. txt".
its files it finds: \steamapps\common\SpellForce 3\bin_win32\configs
remember to make a copy of the original file