It was originally 5th level (I think), but reduced to 1st in SC. You're right that the cap is 1/2 CL, though. So a CL20 wand would cost 15k, and give you at most a +10 bonus to an attack, skill, or ability check, for up to 4 such rolls within the duration (1 rnd/CL, stadard action casting time). It's a pretty good buff, but I guess not too overpowered (probably should be at least 2nd level, though...). So I think I'll allow that one.
In the Tome rules, they basically reduce the amount of bonus types dramatically, though (which I like, but hadn't really strictly enforced). So I won't allow stacking a bunch of different effects with different bonus types onto the same thing to uber-buff it off the random number generator... I wish I'd laid this out more plainly in the beginning...