We stayed at the Mille Stelle in Heidelberg for one night while making our way from Fussen to Oberwesel. While the hotel doesn't have it's own parking, it wasn't difficult to find a spot on the main street (that was free until 8am) and then the hotel had a voucher you could put in your windshield to pay $10/day for street parking.
When we first walked in the hotel looked a little more economical than we were expecting, but we were only there for one night, so no big deal. We had booked a family room for us and our two teens. When we got to our room it was HUGE. At least 15 foot ceilings, two bedrooms, a dining area, separate kitchen, bathroom with a separate shower room. Basically an apartment.
The furnishings were simple, the beds comfortable, the floor was very creaky (but it is an old building so to be expected). The rear door in the room didn't open but appeared to connect to the staircase for the rest of the hotel. We weren't concerned at all safety-wise, but it was a little noisy in the morning.
The location of the hotel was further from the city center than we would have liked but that was no fault of the hotel. This would be a great place for a family to stay for multiple nights. Especially if you want to cook any of your own meals.