The 3-4 tends to be a stronger D against the run. BB has commented on the 4-3 as a slightly better formation for pass defense.
I have doubts for the 4-3 compensating for Wright, against Houston he is drawing double-teams consistently in the tape I have watched. In limited reps earlier in the season he also drew double-teams. If the Jacksonville C is unable to handle Wright one-on-one, then one of the ILBs should be unblocked. Houston also doubled one of the the DEs depending on which side they tried to run to, Warren more than Seymour as I saw it, but this also takes away another blocker from a LB. The other disadvantage to the 4-3, you replace one of the faster LBs with a slower DL.
I expect Wright to work out fine inside on the nose, Vince played poorly over the first half of last season, trying to do to much and over-pursuing. He improved over the second half of the season to the point where he was plugging things up very well. This year he's had his bad plays, but he is doing quite well. Wright is more disciplined inside than Vince was to start last year, even though he may not be a stubborn a plug in the middle, he still forces the OL to work around him, giving the LBs and DEs a chance to fight off their blocks and make a play.
I believe in Wright, I note BB speaks well of him every time he is asked, no hedging as he will for some who have been noted underachievers. Think positive!