Yeah, I agree. The D20 system sounded a little better.
I just read an interesting take on a house ruled Dark Side mechanic. When you want to draw on the Dark Side, you earn a DSP and then roll a D20. Regardless of the roll, the value is treated as a 20. But, if the roll of the D20 is equal to or less than your current DSP total, you have to use that value until you spend another DSP to draw on the Dark Side, calling for another roll of the die. Each time you do it, the automatically generated value is reduced by 1, so a 19 the next time, then an 18, etc. I think the last part might be a little difficult to track, so I would probably change it to the value you get from the Dark Side die being treated as 21 - your DSP total. I haven't really thought about it at higher levels, it might be broken if you can effectively Take 10 or higher for all checks as a character approaches full consumption. Then again, bounded accuracy may ameliorate that to some degree. I'd probably also consider making it so you can only buy off one DSP per level. But then, I'm not a huge fan of grey jedi stuff.