Hm, that's surprising. :\ Most skill-type rogues tend to be at least mildly dashing. Do you actually want the skill mastery-like ability, or do you just want to get into the PrC. I'm perfectly fine with waiving that requirement.
And, in any case, the skill mastery ability doesn't really have anything to do with your skills either; it doesn't grant any kind of bonus. What it represents is the surety and confidence necessary to do something exactly how you were trained to do it in adverse conditions.
Failing that, I think the Int-based one would be okay.