I would guess the Detroit crossing would be the fastest and cheapest considering toll roads. There is a Sams Club for overnighting at exit 37 SBD I-75. That's the first-easiests and safest one to get to I can think of.
As far as "must see", that depends on what kind of things you like ie.: museams, nature, opera, plays, ball games, hiking, etc., etc., etc.