I've hiked North a few times. You can only camp in designated spots on South that that doesn't appeal to me.
Not knowing your physical condition, I'd still rate the hiking as basic to slightly intermediate. As stated you really can't get lost but can miss the ferry. There is a lake in the middle of North which is a good base to filter your water from. The fishing isn't all that great. Remember, the only fires allowed on North are in the designated camping area fire rings in the village.
Two things that I suggest..
NEVER go over a holiday as it is crowded and touristy. People see to be everywhere except for the most remote, off trail spots.
If you can plan your route, and if the morning you leave is going to be clear, pack up early and be on the beach before sunrise. It is one of a very few places that you can watch the sunrise over Lake Michigan while still being in Michigan.