I believe TJ will declare, but a mid to late draft pick. If he weren't a RB, I'd say he comes back. I haven't seen where he ranks in draftable RB's, but I wouldn't think he would be in the top 5. Gurley, Gordon, Coleman, and Abdullah should all be higher than TJ. Assuming the top 2 RB's are taken in the 2nd RD, TJ might be 4th -6th RD pick. Unfortunately, as a RB, wear and tear of another year in college can/will hurt draft stock. I hope he has his degree if/when he does opt to declare.
I really hope Ragland comes back. He will be the most important piece for next year's defense. Foster just isn't smart enough or technically sound enough to lead. Dion-Hamilton is just young and inexperienced.