Much better, not perfect but way better than 12.
I have seen cpu teams switch to 34 and actually cut or try to trade off smaller OLBs. They will use smaller DTs at NT until an actual NT becomes available.
Biggest improvements are in gameplay. Left side still overpowered but LBs get to the QB way more than Dline. Blocking animations still not right but Oline will double up on a NT, even seen em double an end on stunts. Looks funny cuz only one olineman actually engages while the other just stands there but still an improvement. LB gap assignments/awareness still mostly wrong.
Legacy issues remain but after 3 seasons of my Steelers franchise I can honestly say 34 teams play like they should as do 43 teams. I even drafted a low ovr 43 DT late in my first draft, moved him to 2nd string RE and saw 7 point increase in ovr rating!!