RailFanning is an art-form; RailFans are the paints - Ayush Kumar Singh

Your argument is clearly flawed....
AP SF is a legendary train but heritage and facility wise it offered nothing new...
The executive library that you talk so fondly off was first put inside the once legendary Imperial Mail, it also had first class dinning cars, state of the art technology and high priviledges with exorbitant fares...
The Kalka Mail was the original Rajdhani...and it...
more...

is the longest continously running board guage train in IR
It had a first class full residential coach and Guest rooms for the Viceroy and his guests, state of the art facilities and a dedicated carriageway built at HWH & KLK, the carriageway stills remains functional at HWH & the present HWH RAJ departs from here...
The Bangalore mail which is even older than the Kalka is another underated heavyweight which often gets burried...
And with all due respect amongst the 4 champion trains that you mentioned, there is a clear winner in the TN SF. It gets unprecented priority for a 110 SF, comparable to the priority that the 130 permitted and much over-rated SK.
And finally, AP got oted by the WR King, the train that arguably (Arguable because it's chief Rival, Contemporary and competitor, the HWH RAJ also receives similar treatment) has the highest priority on IR tracks....
And BTW, not to offend you... correct me if I am wrong but AP Express started off in 1976, by then the King had been burning the tracks for 4 years :P