Just a tip here. Do include NG routes in your plan too to make it even more fun. As per my li'l knowledge I can suggest you a few existent and according to me better than the rest segments of MG/NG in India.
* BE-ASH MG (NER)
* ADI-UDZ MG (WR)
(these two are the ONLY two sections to have air-conditioned sleeping accomodation...
more... on MG. Pic 1 shows that cute 2A coach)
* Jabalpur Balaghat Satpura Express- NG (SECR) (Check the FC of this train in Pic 2 (Cortesy:
click here ), Isn't it tempting?)
* 15695 LMG-AGTL Passenger OR 05697 Hill Queen Express (NFR)
* For NCR you can take the NG from DHO or GWL.
* For NR it has to be Kangra valley Passenger from PTK.