Kamayani Express - Late आना है काम तुम्हारा लेकिन मैं फिर भी हूँ तुम्हारा दीवाना - Aman

PNR prediction was a major and bulky section which could well be identified and hence, has already been separated. Still if you see, a lot of inquiries are there in the main section about PNRs.
Railways is such a vast subject that Categories will divide into further categories and categorisation itself will become cumbersome.
You yourself have written a number of sections and only at one blink, I could thought of a few more:
Train...
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Types (Rajdhani, Shatabdi, Duronto, GR, Yuva, Jan Shatabdi, Jan sadharan, Mother, Mail Express, Passenger, superfast)
Loco (Diesel, Electric, steam/coding)
Loco (Passenger, Goods/coding)
Coaches (Type, Class, capacity, make, curtains, colour, compatibility, coding)
Platforms
Pantry Cars, Food quality, food available enroute, whether food is provided
Speed
Reservation (Tatkal, Genral, Booking time, opening time)
Reservation basis (GN, GNWL, RSWL, PQ, PQWL, RLWL)
How to book ticket - Counter and Net
RAC
W/L confirmation
Quota (different types, eligibility)
Concessions
Schedules, Halts, Time Keeping
Safety
Lost / mutilated ticket
Boarding change
Reporting after boarding point is left behind
Dog or Pet carrying
Luggage booking
Please suggest which classification/s would you like to have.
Thanks!