Clowney is a vet and would be better holding up against the run on early downs, instead of having Fowler and EZ in there. To keep these two fresh, why not have them come in on passing situations to rush the passer. Doing this should help them in the long run give us more. It's a thought, who knows what could work at this day and age!!
The pass rush hasn't exactly been lighting it up, so yeah I would plug Clowney in as the starter in place of Fowler. They just have to find ways of playing to each players strengths. I would get Ezeiruaku to come in as a blitzing linebacker in packages, then use some combo of Clowney, Williams, and Kneeland in base, then rotate in Houston and Fowler. Even though Houston may be the most productive with his limited playing time I would imagine he's the player that becomes inactive in how they're playing everyone right now.
Williams: 59% - 8 tackles, 1 tfl, 5 pressures
Kneeland: 44% - 7 tackles, 3 tfl, 1 sack, 1 pressure
Dante Fowler: 41% - 1 tackle, 4 pressures
Ezeiruaku: 40% - 3 tackles, 5 pressures
James Houston: 20% - 6 tackles, 2 tfl, 1 sack, 2 pressures