Thank you for this much appreciated
A few more tips for you.
Most Spring/Summer Sunday mornings there are many local villages that have what we would call a Car Boot Sale - except they go on all day! Plenty of food/ices/creps/beer/fruit & veg all at good prices and many many bargains to be had. The local TI office at the back of Obernai Town Hall will give you a free printed list.
Visit the Roman church in Rosheim, the Abbey at Mont St Odile (fantastic views, cafe and restaurant with good food and not expensive), and Molsheim where they build Bugattis and have a rally first weekend in September. If you want to see such, there is a former German Concentration Camp at Natzwiller west of Obernai - the only CC in France. It is in no way horrific but worth a look if you are over that way.
For a trip into Germany with some R+R, take the 426 from Obernai to Erstein then cross the Rhine river/canal (see the HUGE locks and hydro plant), follow the road until you cross into Germany and onto the L100. Where the road does a 90 left go straight on and it will bring you to a boat launching place with plenty of parking and seating (and huge swans!) where you can sit and watch the traffic on the canal/river. Very relaxing.
When you leave there go back to the L100 and turn right, then head north to Offenburg on the A5 (free) and cross back into France and Strasbourg.
If you go to Haguenau head to Roppenhiem which has a MacArthurGlen Outlet-type place very close to the Rhine crossing into Germany. A real eye-opener!
Good luck. Mail me if you want more info. It is an area we visited several times and thoroughly enjoyed.