On first thought, no.
On second thought, FUCK NO!!!
On third thought, OH HELL FUCKING NO!!!!
Fisher was content to play guys 10 yards off the line on 3rd and 3 and let us get picked apart for easy throws and easy first downs. He loved the whole bend don't break mentality and letting teams slowly work their way down the field on the theory that the more plays they ran, the more likely they were to make a mistake and we would get a turnover. But when they didn't, they scored and kept our offense off the field and put more pressure on them. No, just no.
I want a D that has the mentality of trying to get a 3-out every damn time they trot onto the field. I want tighter coverage and no gimmes. You won't get that with a Fisher D.
As for Wade, I'm still undecided as to whether he should stay or go, but I'm really not up for a switch back to a 4-3 now when our personnel is built much more for a 3-4 - especially with a lack of draft capital. Guys like Obo, Ebukam, and Greg Gaines among others are much more suited for roles in a 3-4 than a 4-3. Fowler is probably the only guy who would have an kind of chance of transitioning to a 4-3 DE, but even if we somehow kept him next year (which I doubt) why would you want to when he's clearly better as a 3-4 OLB?
I would much rather the D find guys who can get it done in a 3-4 than have to completely overhaul our defensive roster again, after we just spent the last couple of seasons doing it transitioning from the 4-3.