Your size boat will work great in waves 2-4, even 3 - 5.
Erie is shallow, but the main portion of the lake you will be going across averages 30' You will not need to worry about the bottom.
Just make sure your radio works, you cell phone is fully charged...in close reach, and you have an extra hand held radio.
I would also run around PC for a little bit to ensure everything is working properly. You don't want to breakdown half way to the Detroit Light. There will not be a lot of boaters on the lake to come to assistance if you need help.