I think Collins is a very rare player, and trying to find the next one may be too high a standard. There's a lot of GMs out there looking for the next one.
The guys who are intriguing to me in terms of their combinations of size, athleticism , versatility and skill set are:
- Bud Dupree: he's got the explosiveness, and I think he may have the raw athleticism of a Collins; I don't know if his movement skills will be as good, and his combat skills may be lacking.
- Danielle Hunter: he's got great length and combat skills for his size, and rare movement skills for a DE; I'm not sure that he has the explosiveness (though he is rumored to have a 38" VJ). He seems to be a bit like what you'd get if you merged Jamie Collins and Chandler Jones.
- Bernardrick McKinney: he's got great versatility and size; I'm not sure he's as fluid in space, or quite as explosive.
Those are the 3 guys who jump out at me. I'm guessing that Manx might include Shane Ray, who is certainly athletic and explosive, though I think his role has been much more limited.
As an example of how hard it is even for athletically elite guys to fill that kind of role, I found this read on Barkevious Mingo interesting:
http://www.cleveland.com/browns/index.ssf/2014/12/barkevious_mingo_browns.html
It's well worth a read.