Finally have time to post these. Thanks to everyone for the recommendations on what to do in case there wasn't enough snow. We stayed at Big Buck Cabin in Greenland. MrsRunningBear, the sled hill was perfect for the kids (and me) at Bond Falls. We arrived to 45 degrees and a front came through that night where had enough snow to do whatever we wanted. Trail 3 out of Mass City was way better than we could have imagined. We took trail 13 at night from Greenland to Twin lakes and while it was a tad thin and had some puddles, we didn't meet another sled the whole way. Overall, we met maybe 20 sleds on our whole trip and got 210 miles on. That may not seem like much, but with the kids, it was way more than i thought. We even took the kids ice skating in Ontonagon as we found outdoor rinks are not plentiful in the UP. (gee, i wonder why).
Overall a great trip and I'll be back up on the 3rd to ride without the kids.