Yet another reason to move back metz...
As for the Buffalo Sites, I'll add:
The Naval Park is pretty cool. And it's pretty nice along the river front.
There are tours of City Hall every day at noon IIRC.
Lunch hour Bands at M&T plaza M-F during the summer.
Farmers market on Main St every Tuesday and Thursday (right next to M&T, so you can do both)
And there is always some festival happening on the weekends...
Lockport Lock's and Erie Canal Cruise or Cave & Underground Boat Ride are both very cool.
Of Course Niagara Falls is worth the trip, but the Canadian side is much much nicer.
Niagara on the Lake- ? Very nice views, shops, and restaurants. It's a bit pricy, but a beautiful area.
Erie Canal restoration site- ? Near the Naval Park, very nice restoration. You'll get to see what's left of the Aud as well.