I am open to constructive criticism.
When losing the cards at 0:21 I like to be a bit more cavalier about it. If I break down my approach:
1. Out jog the 4 cards.
2. Fan them so it is clear they are in different places.
3. Square the fan with the backs to the audience
4. As you rotate the deck face up execute the block displacement.
This helps to make the displacement a bit more fluid. If you don't like it than I'd just work on making it a bit more smooth.
Also, you don't need the riffle shuffle. It's fine, but your audience already saw you lose the cards convincingly and Hindu shuffle. A better option might be to subtly "prove" that the cards aren't in an obvious place like the top or bottom. You can show the bottom stock of the deck very casually here if you'd like, they get the idea that the deck isn't in any order and it gives you a little time in between losing the cards and finding them.
While I'm on that, why produce the cards, only to lose them then to find them again. I'm missing the context. You could start with a few shuffles then find them from a shuffled deck. You don't have to lose them first.
The best versions of this type of trick have a reason for each production. Your first production is the best but I'm not sure what is supposed to be happening. What is the trick supposed to demonstrate? How you can change any cards into other cards? How you have control over the deck? How you can call the cards out at will?
When you get specific you will see your magic get a ton better. Focus is key.