I'd say it more of an issue with your hand size vs. system size than it is with actual button layout. I think the slide pad is great, personally (if only they had incorporated two of them right from the start). I felt more comfortable with the original DS size than with the much smaller 3ds, but it is meant to be compact and able to be carried around easily. I think they have managed to balance the issue somewhat ok and I'm happy with the product once I got used to the feel. ...but perhaps for people like you or myself, a 3ds xl wouldn't have been a bad option right out of the gate or perhaps down the road a bit.
Another thought would be that rather than a 3ds xl being the answer, perhaps people with larger hands (and adult gamers) should look to the circle pad pro accessory to be the answer for better grip/comfort. I know I like the concept and am getting one.
