Imad Wasim has very good batting record in ODIs. His bowling is average and he seems like more of a batting all-rounder.
Look at it this way
Shaheen is our gun bowler with the new ball
Shadab will get us wickets in the middle overs
Hasan will pick wickets with reverse swing (after 35 overs)
Both shaheen and Hasan would be used in different short intervals of the innings to make the attack penetrative
Amir is a reliable bowler who would give us control with the new and old ball
Hafeez and Imad would provide the control for shadab to pick wickets in the middle overs,.
In a game against India, faheem can be used as a stock bowler. Since,
Faheem is one of the best death bowlers in the world atm (yes you read that right ), Hasan and shaheen can even bowl their death overs at the start to keep the Indian batters at check.
The balance of the attack looks perfectly fine.
Imad is the best option we have rn as our 2nd spinner, the likes of Nawaz can't bowl outside UAE and are awful with the bat. Imad is decent for true pitches like England and SA (he is not a powerhouse, but can be a handful in SENA).
PS: Faheem is also going to surprise you guys, his style of play is suited to the kind of pitches he will face in Eng, I know he is awful against spin, but it ain't gonna spin extravagantly in England.
PS 2: The kind of control that Faheem has shown with the ball has put Amir's future in real danger. If Faheem can achieve his batting potential, then he might as well replace Amir as the necessary reliable bowler in our side. Amir's future is in being an all-rounder.