Ndls, vsg, sc all are good n I think all routes are capable to fill hs.
Mumbai have 5 day Duronto n other too. Mumbai route can fill hs in peak season only as I know seats in Duronto is easily available(in non peak season). My friend booked ticket recently day before journey that time more than 200 seats were available.
Can't say about Mangalore.
Bhopal...
more... can't fill HS to Kolkata. Normal SF is good here.
**Though RSA pattern may not feasible in respected routes cuz of running days.