Road Trip Brainstorming

I want to plan a trip for my next stretch of vacation days. 
I'm thinking of going south along the St. Croix:  Hastings, Red Wing.  I don't think I want to go all the way down to Wabasha though.

I've only driven through these towns once and I was half asleep.
I'm wondering if any of you have any recommendations on things to do in this part of Minnesota.

Do you know of a hidden boutique somewhere?  Or a great hole-in-the-wall restaurant?  Ever been to Treasure Island?

Someone mentioned the I could do a trip down on the MN side one day and coming back on the Wisconsin side the next.  If I did that, I would also need lodging.  Something cheap.  I don't need the honeymoon jacuzzi or kiddie pool.  Clean sheets and polite staff.