I don't know when the season starts, but look out for fishing nets out in open water. We've just been running along and found ourselves surrounded by bleach containers and buoys that hold up the nets. Keep a look out even when there's nothing around to see. Probably don't need to say it, but as always, you gotta have a chart and a gps should be required for that trip.
Where are you bringing the boat home from in Lake Erie?
Like Bill said, watch out for the fishing nets, usually on the CA side of Lake Erie between Put In Bay the Detroit River. The jugs are holding up nets which are usually 6' + below the surface. I've gone between the jugs before without a problem. Don't freek out if you see them all over the place!!!
River is fairly simple to navigate, there are just a couple of areas downriver you will need to make sure you stay inside the channel as it gets shallow outside the bouys.