The welding on the upper control arm bracket looks great.
The traction rod pivot bracket is much stronger with the gusseting in place.
The toe rod mount is now much stronger and flex-free.
Here is the other gusset on the other side of the toe rod mount.
These 4 heavy cast steel weights serve as mass dampers. They are welded to the cross member. Nissan added these to reduce NVH. Since this is a track car, we don’t care about minor NVH issues so they had to go.