This team has entered its "window."

HC and QB are in place.

I don't necessarily think TL will continue on this insane pace he's set in NOV/DEC, but anything approaching that means long term success in this league.

That said, the next step is affording TL a cleaner pocket and a tick of the clock longer to operate. He is under pressure often and early. He's just so good at slipping away from it - folks don't notice. But that's not a sustainable/long-term way to build a dominant offense.
Find a way to allow him to step up into a pocket more often instead of being forced to relocate less than 2 seconds after the snap and his longevity will benefit - as will his production.

In the short term - they need an interior guy to round out the front, and then they'll need a tackle when cam is done.
I'd try to find a guard that has some experience at center and let him compete with Bartch and Fortner in camp.
Whichever spot is weakest gets the upgrade. Fortner is a rookie but he looks weak at the point of attack and gives up lots of pressure too quickly. Bartch is expected to be solid - but a bit of a question mark. This would also improve depth at RG where we know Scherff is playing through injury right now and rarely lasts an entire season.
TE is the only other piece on offense in dire need of a solution and we all hope it involves a deal for Engram.

Moving to defense, which is more the focus here, they need another corner or nickel.
I think given the current cap - you roll with Campbell and Williams outside and try to find an impactful nickel in the draft.
Many of Campbell's stat lines this year are bordering elite level of play. He's the real deal. 
Williams looks more comfortable outside, but we have a bit of a small sample seeing him outside in this system.

Next phase of defense in need is the pass rush. Adding a quality nickel and keeping DW outside will help buy the pass rush more time to get home, but I think an interior disruptor is key. They need a 3-4 end / 3-techDT guy that can collapse pockets and flush QBs laterally to the EDGE guys.

Could they upgrade Josh Allen? Probably. And I imagine they will, but I'd hold on spending big capital on that till 2024 and try to help Walker and Allen by adding some heat on the inside. No guarantee you get Smoot or Key back, and they need a guy with more consistent pressure from that spot if they can find one.

I'm not worried about ILB. Let Lloyd develop and the chips can fall where they may between he and Muma. 
I hope they get creative and find ways to utilize them all.

Regarding standout defensive playmakers: I think we have a chance at seeing any number of guys rise to that role.
Possibilities include: Walker, Lloyd, Cisco, Campbell, and hopefully a 2023 draft pick.

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