Here is my personal perspective on this, as I have lived for a few years in the area in question when I was a little kid.
Satpura Railway fell victim to the uni-gauge project and the desire to provide modern transport infrastructure to this backward area. What happened is the viable parts of it were converted to Broad Gauge, or are being so converted, and the rest is being retained as is. Looking at the Indian Railway Atlas 3rd Edition I see, that there is only one small branch that will remain NG. The rest in its entirety is getting converted to BG, and at least one trunk (Gondia - Chanda Fort) which has already been converted to BG is now getting electrified (25kV, 60Hz), as it provides a good freight by pass of the Nagpur area congestion. Nagpur is where the East-West Kolkata - Mumbai via Nagpur and the North-South New Delhi - Chennai trunks meet. The network that is or has been converted to BG, which consists of:
Gondia (on Kolkata - Mumbai via Nagpur route) - Naghbir - Chanda Fort (on New Delhi - Chennai trunk)
Gondia - Balaghat - Nainpur - Jabbalpur (on Kolkata - Mumbai via Allahabad route)
Balaghat - Katangi - Tirodi - (Tumsar Road on Kolkata - Mumbai via Nagpur route)
Nainpur - Mandla Fort
Nainpur - Chhindwara - (Amla on the New Delhi - Chennai trunk)
Chhindwara - Itwari(Nagpur)
Itwari (Nagpur) - Naghbir
Additional new BG lines to fill out the network in this backward area are being constructed as follows:
Sridham (on Kolkata - Mumbai via Allahabad route) - Seoni - Ramtek - (Kanhan/Nagpur)
(Nainpur) - Mandal Fort - Jabbalpur (on Kolkata - Mumbai via Allahabad route)
(Nainpur) - Mandla Fort - Bilaspur (on Kolkata - Mumbai via Nagpur route)
So all in all this is a massive infrastructure improvement project in an area that was so far very poorly served (no wonder the trains were overcrowded).
All this is sort of near and dear to me since in my very young days we lived in Bhilai, where back then the massive Hindustan Steel steel plant was being built back then) a little east of this area. This area was unbelievably under-developed and poor. It is good to see such massive investment in improving the lives of all these people.