I get what you are saying, but Wahab has not been played in international cricket in two years (which actually goes against his selection, I appreciate) while the likes of Shinwari have had a downward spiral, starting well but struggled terribly of late.
It is indeed sad that Junaid was dropped based on a few matches' performance. Poor guy get a chance after ages and he gets axed in no time.
I am hoping against hope Wahab will bowl a consistent line and length. There is no question about his pace, but it's the consistency he lacks that could be so valuable in the middle overs (I am reminded of his spell against India in 2011 WC)