Ernest Jones is the starting MIKE. He's a proven veteran. Weatherford has been waived. IMO this quickly usually means he didn't pass the physical.
Zach VanValkenburg is an interesting prospect if they play him at ILB like I think they will. Hes got good size at 6'4" 263 lbs. He's the kind of ILB you want sitting in an A gap. More likely the second ILB is likely to be Rozeboom. Another rookie who might work his way into the mix by starting out on STs would be
Kelechi Anyalebechi he's a bit undersized and raw but he's got decent speed and athleticism, a good work ethic and will play like his hair is on fire. He's a two year project but he could have value initially on STs.
Bobby Brown is an early down 0T NT who as a two gap DL is supposed to eat blockers to keep the LBs clean. On passing downs they rotate Murchison in to play a 1T NT. IMO with Murchison there is no need to play a two gap 0T NT. That said Morris then plays only one ILB behind him. That is dumb. If you are going to play a 0T NT you need two ILB to cover the A gaps. Morris claims he does it to keep them from double teaming Donald, but then he has AD not attack but play read/react. This tells me Morris really doesn't know how to coach. He might be great at calling plays but he sucks at coaching and Jalen knew it. Playing the DL like that with only one ILB is an open invitation to run power through the B gap which is exactly what SF does and Morris is clueless. The LT walls off the inside from the DE, the LG and C double the 0T NT and the FB takes out Jones. It's there for SF on every first down. An easy 4-6 yards on first down. This is why they need an OLB to play WIL to discourage that.