Nürnberg is a good choice. You visit Bamberg for the town more than the market. Würzburg for its market, Archbishop's Residenz and the Castle across the river. Rothenburg for the great photos you will get.
http://mcchelsea.smugmug.com/Advent-2010/Rothenburg-ob-der-Tauber/15010043_Ck957T
You might also consider Regensburg which we like best for its combination of the market and the town, a UNESCO World Heritage Site (as is Bamberg).
http://mcchelsea.smugmug.com/Advent-2010/Regensburg/15028020_t5NQGm
http://mcchelsea.smugmug.com/Advent-2010/Thurn-and-Taxis-Palace-Market/15030947_4WtqMc
From Regensburg Landshut is a great day visit. Very attractive small town.
Finally, consider Stuttgart. I has an enormous market like Nürnberg and can be very crowded at night. It has regular train connections to Paris. Consider a day trip to the beautiful town of Esslingen with its Medieval Market.
http://mcchelsea.smugmug.com/Other-1/Esslingen-2013/35504333_SfNrdp
Wonderful time to visit Germany.