Improving is a loaded term. A big part of the defensive failures this year is pure execution. If the question is modified to if he is changing the D to help cover deficiencies, then yes. If you rewatch the first series against Rutgers, he is running single-high safety the entire drive, with Brown as an 8th man in the box. They were beat over the top on a pass play, but Lovie decided to get aggressive and make Vedral beat them in the air, which he did.
The next drive, he was back in the 4-3 Cover 2, but with Derrick Smith at the Spot Brown was in before. He followed that up by going back to the 8-man box after the turnover.
Lovie is doing things to try and force the offense to respond. I don't sit in practice all week, so what we see on Saturday is how things are graded. He is making changes, and not near as basic as we believe in general. The execution though leaves a lot to be desired.