OK, that's fair.
I'm not a fan of Bass. He has not been able to stay healthy two straight years, which makes me wonder whether he can physically hold up as an interior player. Going back to Texas A&M, he wasn't particularly productive there (only two years of experience on the DL), so there's not much to feel hopeful for other than the dreaded P word (potential). McClain has washed out with three other teams, and the team that picked him in the third round, the Panthers, let him go after one season. That almost never happens. Placing a lot of stock in either one of these guys is a strategy of hope, and that is not typically a recipe for success.
At end, I like Lawrence a lot, but he is going to need time to adjust to the physicality of the NFL. As a situational pass rusher, he can be a solid contributor, and with some time in an NFL strength and conditioning program, I like his future. Selvie is an OK player, but one that you would always look to upgrade. Anything Spencer contributes is gravy due to his injury status and not playing in a 4-3 defense since his senior year at Purdue.
The LBs are fine, though Lee cannot be counted on to stay healthy for a full season. Carter needs to be pushed heavily, and hopefully Holloman can do that. Wilber/Durant are OK at SLB.
The big concern with this defense is that there are no real upgrades of note at any position, and this defense was personnel deficient a season ago, especially up front. They are also putting a lot of stock and faith in guys with serious injury issues (Melton, Lee, Crawford). I don't see where this defense ends up being significantly better than a season ago, although it would be hard to be as bad or worse.