I am fairly confident that a rotation of Ayers, Wolfe, Malik Jackson, and a potential FA/draft pick could still be pretty effective rushing the passer. This is especially true when you have a top 3 pass rusher in the league Von Miller commanding a double team constantly. It's not going to be the same type of individual production, but still pretty good.
On the other hand, Revis is a once in a decade type player, he's still in his prime and should be a top flight CB for another 3-5 years. He's basically prime Champ Bailey. Champ in his prime probably had slightly better top end speed, but Revis is better at jamming the line of scrimmage. In terms of forcing turnovers, Revis basically shuts down half of the field and would allow our other very good on ball defenders like Champ to ball-hawk and choke up on TE's in the slot. Basically, Champ could play up in run support and take away a ton of the shallow crossing routes and TE drags that teams like New England kill us with. Plus with Revis on the field, you can provide Champ with help over the top with speed receivers as he gets older.
It would suck to lose Doom, but long-term I think Revis gets us closer to the SB. You can find situational pass-rushers in every draft and in FA. Truly top flight CB's?
Woodson in his prime, Champ in his prime, and Revis. He's that good.