Well, this is quite impressive as far as train travel goes (ok, I wish BHD Belle had done a report on his/her trip). I am also a train buff.
I did the Frankfurt to Brussels & Zurich to Chur (in December, snow scene was fab). Chur is a great little place to stay. In fact I used it as base while day tripping (one day Glacier Express & one day Bernina Express).
Look forward to the rest.