Thanks for the responses. Half her ring finger span is probably 2.25 inches or thereabouts. The ball has a 2.5-inch pin so that's probably close enough.
The ball will be a Hammer Raw Acid, which comes at 4000 and no polish. We're going to try a variety of surfaces to get the desired aggressiveness. The reason I'm considering a Rico drill is that, if it's anything like the ones I've thrown, the ball will be fairly early and very even and predictable.
Her other two balls are both pin-up with the CG (and thus, the theoretical mass bias) kicked out to the positive side. One of them is a little too skid-snappy and the other ball (the SSSE) just has too many games on it. It's been resurfaced numerous times.
She typically struggles on fresh due to her rev rate, then gets better as the night goes along and she can see more friction.
It's either Rico or it will be pin-under-bridge. My biggest concern was hitting the holes with the flare rings.
Jess