this is not easy 11 to pick because of constraints: 
1) if we consider sharjeel/fakhar/babar + 1 wk we are left with only 7 options who could bowl
2) Faheem Ashraf is a proven dud with the bat (never seen him scoring more than 20 runs except those rare test innings, and he is absolutely worst in bowling, always get Phainta like Agarkar)
3) All rounders : Imad and Shadab are bits and pieces All rounders, but then we have no choice. Amir Yamin/Amad Butt trundling would be eaten alive by any team, so definitely I would not waste 2 spots for weak All Rounders, no matter how great they are at domestic, but so far Amir Yamin and Amad Butt has not shown any promise.
So we are left with 2 realistic choices in Imad and Shadab [ they can get 8 overs for 50/60 runs with may be 1/2 wickets between them, and can get 30-40 runs in total] So the idea is to maximize their limited potential. This also leaves with option of selecting Hafeez if and only if he can bowl in T20 WC. Malik does not bowl these days, and is ever so pathetic batting wise in SENA countries. Though he is a good fielder, so should play as 12th man 
4)Wicket Keeper : Options are Akmal, Sarfaraz, Zeeshan Ashraf, Rizwan
Rizwan : Takes time in T20, so defeats the purpose. Not needed.
Akmal : Domestic bully. Will almost always fail against more than average teams. Plus he is very unreliable as a WK. Watch out for catches dropped/ missed stumping or run outs if he luckily plays. But should be no where near the team.
Sarf : When Sarfaraz was dropped from the team, I think Misbah, Waqar and management made up the mind that they do not want to take Sarfaraz to T20 WC. Else he would not have been dropped. Unless he plays some outstanding innings (which so far we have not seen). Realistically, he is not going to be part of T20 WC.
Zeeshan Ashraf/ some one else : We are left with only some trump card of wicketkeeper. So whoever gets selected, will be a big responsibility.
4) Openers : Plenty of them (Sharjeel/Imam/Fakhar/Babar) I think realistically Sharjeel-Fakhar-Babar would be top 3 depends on their batting positions on how they bat
5) Fast Bowlers : Plenty of options. But big No-No to Musa Khan ( he always get spanked, and knows only to bowl short-pitched deliveries). They should recall Amir/Wahab. 
So based on the above constraints ,I think below is the best available option
Zeeshan Ashraf
Sharjeel
Fakhar
Babar
Shadab
Imad
Hafeez
Hasan Ali
Amir
Wahab
Haris Rauf