Rgeo actually Divine DIvinity was pretty good, yeah its kind of old now, but it really was not bad at all, I played through it at least 3 times.
But yeah I agree D:OS is a much better game.
The unfolding skill-bag idea isnt bad, I admit I like the skillbar as is, but that does not mean it couldnt be better. I would have just suggested making the rows 15 spaces long or adding 2 more rows for a total of 70 spaces, but your idea sounds better.