You can see similar towns as you make your way along the Mosel and Rhine Rivers toward FRA.

Cochem is less than one hour from Trier by train. Lots of "Fachwerk" (half-timbered) houses, old town walls, towers, cobblestones, Reichsburg Castle and falconry exhibition on castle grounds, river cruise options, wineries, cool chairlift ride. Moselkern, the trailhead (easy hike) to Burg Eltz castle, is a few train minutes further downstream. I'd spend 2 nights there.

http://www.cochem.de/tourismus/en_index.php
http://www.cochemer-sesselbahn.de/en/index.htm
http://www.falknerei-reichsburg-cochem.de/fotobuch.htm
www.burg-eltz.de

St. Goar is easily reached by train from Cochem with a change in Koblenz (medium-sized city and major train hub for the area) in under 1.5 hours. The villages of Bacharach, Oberwesel, and Boppard are also old-world villages with wineries and great scenery and only a few minutes away. All these places lie in the UNESCO World Heritage-designated Middle Rhine Valley, where 40 castles can be seen in 40 miles of river, either by boat or by train. All these towns are great, but St. Goar makes a good base town if you want to see Marksburg Castle in Braubach (cross the river by ferry from St. Goar and take the train north 20 min.) which has a very good tour.

http://www.st-goar.de/17-1-rheinfels-castle.html
http://www.marksburg.de/english/frame.htm
http://www.welterbe-mittelrheintal.de/index.php?id=274&L=3

You can reach FRA from St Goar in 1 hr. 15 mins. Or base yourself in Bingen, south of Bacharach, and readh FRA in about 50 mins.

Train service is great for all destinations mentioned above. Get a group daypass (Rheinland-Pfalz ticket) for the local area. For two, it's 26€ per travel day (covers regional trains from Trier and the other towns all the way to Mainz - see map on following page; Mainz to FRA costs a few Euros.)

http://www.vrminfo.de/en/tickets-and-fares/ticket-offers/rheinland-pfalz-ticket/

Thanks so much, Russ. I am going to look into all your suggestions. I was all over the map (kind of) in the towns I mentioned I wanted to see. It seemed like we would be on & changing trains a lot. Love trains, but time is limited in the area....unfortunately. I so much appreciate your responses.

I'd stay where you are and visit
Luxembourg city
Trier city
Take a train and ferry down the Mosel
All this could be done by bicycle as well.

If you want a very nice hotel I'd try and get a cheap deal at Beckers in Olewig www.beckers-trier.de‎ but through someone like booking.com . Their traditional rooms (plus breakfast) are very good value while their new building prices are just silly. The brasserie at the end of the street does good food and home brewed beer while the various wineries on the street are interesting.

Russ gives great advice as well and PalenQ and the Cowboy may pop up with some thoughts yet.

Is Schwabisch Hall worth a visit? Thx

YES