30 mins doing UK, Gundrak and Drak'Tharon is what you should aim for, and thats including killing all and looting without rushing or feeling stressed.

If you want to do it faster it starts to become a gear question

I have a routine for all dungeons i rarely use short cuts except in gundrak after killing Eck but i dont leave trash cause as i said i like to collect the money n mats

PoS still takes about 1h to finish and i rarely go throu it without a whipe or 2-3 deaths