My opinion about extensions:
1. Link express between tirupati and h.nizamuddin as malkajgiri link via dhone, kurnool city in place of apsk express instead of current visakhapatnam h.nizamuddin as kazipet link and make dakshin express via nizamabad & adilabad.
2. Introduce APSK Express tri-weekly between tirupati & jammu tawi or katra via new guntur, warangal jn, new delhi, amritsar & bi-weekly between tirupati & chandigarh or kalka via new guntur, warangal jn, new delhi, & bi-weekly between tirupati & dehradun or haridwar via new guntur, warangal jn, h.nizamuddin, meerut.
3....
more... Introduce Swarnajayanti express tri-weekly between guntur & jammu tawi via eluru, visakhapatnam, raipur, usalapur, bina malkhedi jn, new delhi, amritsar & bi-weekly between guntur & chandigarh or kalka via eluru, visakhapatnam, raipur, usalapur, bina malkhedi jn, new delhi & bi-weekly between guntur & dehradun via eluru, visakhapatnam, raipur, usalapur, binamalkhedi jn, h.nizamuddin, meerut
4. Introduce samata express between visakhapatnam new delhi via raipur, usalapur, bina malkhedi jn. It should be daily & it's one of the shortest distance compared to present route.
5. Introduce AP AC SF express between visakhapatnam new delhi via raipur, usalapur, manikpur, kanpur, noida & ghaziabad. It should be daily & it's very shortest distance between the two cities.
6. After getting rajdhani express, it can run between guntur or vijayawada to new delhi via warangal jn which is short route.