1. For the most part, yes, there’s lots of good exercises here. But it looks a bit unbalanced to me, although it depends on your goals. There are some things I would change.
2. Most of it. I don’t feel comfortable saying I can do a V sit or tuck planche. V sit I really need to work on my pike, and for some reason I always had trouble with any kind of direct planche work. My uncle could hold a tuck planche easily but in just about everything else he’s weaker than I am (last I saw him). Dunno about doing a set of 20 pseudo planche push ups with my feet elevated either, that sounds hard.
3. Anything’s possible, but those examples you gave are highly imbalanced. If you can do a 20 second L sit you should be able to fly past 20 push ups and 3 pull ups.