I'm not sure how popular such an idea is, but what about adding a key to put the cursor on a random skill when leveling up ? (I'd choose "*", as default).
I sometime wanted to play with the challenge of not choosing my skills... but since the game doesn't handle it and I was too lazy to tab to random.org at every level, I never tried it.
I think it's both easy to code, and a good way to let people change their builds on a semi-random way. (needs to propose the skill, not choose it, so that you can avoid one you really don't want).
What do you think ?
EDIT :
@ParaSait Already tried it, but it's slow, and often selects a grayed skill. Not convinient at all.
Making an angel of it seems too random to me. Rolling SoB and HR is very different from TaN, Iro, or a single level of brute :p
The main idea is to give a simple and fun way to increase your challenge on demand. Only at level 1, or every other level, or all of them... YOU choose !