All comments so far sound good. This is what I notice.
1) With many of your serves the contact point is obstructed by your body even from this angle on the camera. That means that to a person standing at the table, probably most of your serves are being contacted with your body obstructing the view of the ball contacting the racket. That would be another way in which the serve is not legal. Your body cannot be in between the ball and the view of the person you are serving to.
2) I would toss the ball higher. 1 foot higher, 2 feet higher would be fine. 3, 4 or 5 feet higher would start giving you a decent amount more spin. Some of your tosses are high enough to be legal but not high enough to help your serve. Some of your tosses might not even be high enough to be legal. Some of your tosses go up only a few inches when they leave your hand and many of those you are contacting before they drop more than a few inches. You are contacting the ball very close to the top of the toss. This is also related to what ttmonster said about contacting the ball lower so that you can keep the ball lower.
3) To me this is probably the biggest issue that I saw, or heard. It sounds like your contact with the ball is too direct. Your racket is making a sound like you are hitting into the ball. That means you cannot be getting too much spin. It sounds like you need to get the edge of the ball more, let the rubber grab the ball but not let the ball sink all the way in to the wood. This way, when you accelerate the bat speed by snapping your wrist you will get more spin rather than speed.
As far as presenting the ball, there has to be a point where the ball is motionless and the opponent can see the ball being presented before you toss it, and the ball has to be in your palm, not touching your fingers. It is true many pros cup their palm, but the opponent has to see the ball. And it is also true that, technically, you are supposed to present the ball with an open palm and the hand flat and the ball is supposed to be in the center of your palm. So both Mr RicharD and WiWa are accurate.
Also, even though you are lifting your leg, it does not look like you are getting much body into your motion. Perhaps having your knees a little more bent to get a little lower to see if you can get the weight transfer and the hip a little more into the action.
I would work on keeping the contact point and the serve low, doing a considerably higher toss, letting the ball fall before contacting it, making sure that your body is not obstructing the view of the ball, making sure you are presenting the ball before you toss it, and trying to spin the ball more. A way of testing this is to try and do straight underspin serves where you are trying to get the ball to come back to the net. If you do a serve and it is really slow and comes back to the net, that is a start. If you can do a serve where you are not really slowing it down and you can get it to spin back to the net because the spin overcomes the speed it has decent spin.
All this being said, the basics of your serves are good and the adjustments should be easy your are doing the fundamentals quite well.