I am a large proponent of the 4-2-5 instead of the 3-3-5, but I think that a lot of our struggles go back to the guys on the field. The 3-3-5 was great when we had a Will McDonald IV, a Jaquan Bailey, or an Eiyoma Uwazurike who can go get you 10 sacks by themself. However, we just don't have a guy like that on the team right now. I like some of the guys we have on the D-Line, but they're being asked to do too much. These aren't the kind of guys that are going to beat double teams, which they are often facing in the 3 man front.
Not only this, but the 2 and 3 deep linebackers we have to play due to injuries are just not up to P4 standard right now. I noted several times in the KU game where they missed tackles and were not in the correct gap, especially while KU was running that speed option play that they kept burning us with. I don't blame them for it; they're young and need time, but IMO, it's a talent issue, not a development issue. You can't teach the kind of thing that Georgia, Alabama, OSU, and Texas are getting out of their kids. There is a clear lack of on our defense, save for a few guys like Porter. Obviously, we aren't going to be on the highest level in terms of recruiting. Still, we can't keep stringing together below-average recruiting and portal classes in the B12 and expect our guys to be competitive athletically. We aren't playing Texas and OU anymore, so we should be on a somewhat level playing field in the conference, aside from the Texas schools. I am well aware that stars aren't everything, but there has been a clear talent gap in the last few weeks. It also seems to me that we haven't been hitting with the highly-rated guys we do get in the past few years.
In terms of right now, I think we should be adding another down lineman and taking out a linebacker. Schemes are built around the strengths of the team, and we are clearly weak at linebacker right now. 3-3-5 made perfect sense when it was implemented, but with the way the team sits today, it doesn't make sense anymore. It's built to stop Baker Mayfield, not RJ Harvey. Teams have figured us out, and we need to adjust if we want a chance to compete for the B12 title. This also applies to the offense, IMO. It is a disservice to keep putting multiple TEs out there when you are stronger at WR, especially with Brahmer out.
TLDR: stop banging your head against the wall