I had a very quick look a few days ago and couldn't see anything of detail. I know the floodlights would need updating and suspect the number of TV camera positions would have to be significantly increased. Then a VAR area. Aside from that, I'd be guessing.
We might be talking about different things here? I'm talking about a major renovation, or even replacement, for the West stand. We can't stay in the 20th Century for ever. That means accepting, and even encouraging a requirement for standing. Shouldn't be too hard. Three sides of the ground will still be for the elderly!