Okwara is a Rush LB (Diaco's CAT)
Jamir is a LB anyways and right now would either be a rush or cover OLB.
Hinish is a tough fit, but I could see him as a 5-Tech. Maybe NG, maybe. I think he's probably too small for the role (but so was Zorich), but I love his strength and nasty streak.
Ewell can be very good NG. Already sitting at just under 300 and he has the frame to put on the weight.
As for who would be our DE's in a 3-4, most likely Jay Hayes, Tillery, Kareem, Bonner, Hinish, Jeter, Taylor. Overall, I think that could work. You don't need 6'6 310 freaks of nature like Stephon Tuitt to run a 3-4 (though it made life so much easier). A guy like Kapron Lewis-Moore became an excellent 3-4 DE.
NG is a bit trickier. Cage would be the likely starting candidate next season. He's got the traits you want in a zero tech. Mean, aggressive and strong. But after him is a big question. Essentially looking at a bunch of guys who have little to no in-game experience like Dew-Treadway, Tiassum and Mokwuah (possibly Ewell, but I'd want to redshirt him and get his size and strength built up).