Talking about not improving... I actually have improved as I focused on more technical things rather than fitness (which I don't have anymore). One of the things I focused on is my sidehop that is rather rudimentary, which makes it easy to improve... 

Here's a video where I focused on the little kick and jump afterwards:

And here's a clip where, at the end, you can already see the fruits of it. I also find it easier to do moves on the rear wheel:

I haven't had time to go out and ride lately as I got a new job. There's no real improvement in this video but I thought I'd still share it.