hokielin, I hope you found a good place for the two of you! Let us know where you decided to go, if you were able to.
I second Windham, Belleayre, and Hunter. For another Catskill option that is less crowded, since it's a little further and is often the "local's hill," you could also try Plattekill.
As for not finding anything for experts within 5 hours of NYC, I'd disagree. Hunter West has some great expert runs, and the trails serviced by the Wheelchair lift at Windham are good, too. Are they wonderfully diverse? No. Are there powder stashes? No. Impressive vertical drops? Again, no. But if you want to run laps and work on your technique in some tough conditions, the runs are there to find. I'll spend a whole day on the Wheelchair lift and still feel like I've got more to work on. It all comes down to what kind of mentality the expert skier in question has. Try skiing those runs on one ski, and hey presto, you've got yourself a super-hard trail!