Some more videos with different angles would be helpful I guess where you show more shots. I think you could try to rotate your torso a bit more. The start is fine but then you stop rotating at the middle and take the speed mostly from your arm.
For more spin you can obviously hit the ball more tangential with a higher curve.
spin is coming from the arm, power comes from the body. I you want to get more spin you need to move your arm faster=more brush=more spin. If you want more power you need use the body more. If you stay close to the table the power is limited because you do not have the time to rotate the body. It is important to relax. Tense arm= hard to move the arm fast when creating spin and the arm will not move faster when you use the body. try to think that the loop is like hinges on the door, the arm, the hip and the legs all move together. Study the chinese and i think you will understad what i am speaking about.
Truthfully, I would say, speed is not your issue. Spin is. But really, it is hard to say from that drill.
v100ev has a good point. Your body and your arm don't sync. To me it looks like part of the issue is that you are too squared to the table so turning your hips would cause you to face the BH side. You may be helped by opening your stance so your right foot is farther back.
All this being said, you seem like you are doing decently well. Multiball drills that require more moving to adjust to the ball, particularly in/out drills that cause you to transition from backspin to topspin would be worthwhile.
You have already got the speed , focus on spin man. Speed is overrated in table tennis ... and spin is underrated .... focus on your timing , where you can generate more power ( both spin and speed ) without putting in so much effort , focus on your footwork that you are able to get into position faster to execute that timing , focus on practicing different timings , A, B, C, D ... ( you can find them in different places in the internet ) and also focus on hitting the sweet spot of your blade every time you touch the ball ... the issue with your waist rotation others have already pointed out ... and don't DON'T GET A FASTER SETUP .... you will lose feeling and even though you will win some cheap points at the onset it will stop your development ...
Now as to your original question ... first focus on increasing the spin and understanding the spin of the incoming ball .. and adapting your loop to it ..
I would say start practicing more loops against backspin , both slow spinny loops , and third ball attacks where you take the ball earlier ... but make sure you mix it up with looping against topspin as well ... essentially , as you increase your ability to spin you should also keep in mind that your loop ( starting position / timing etc ) should be able to adapt to incoming ball ... once you get that and once you are able to start placing your loops on dime , then think about speed ...
when ever my brains goes all speed demon , I keep telling myself to remember that in table tennis the one who wins a point puts one more ball on the table than the opponent with smart placement , and spin actually helps you do do it , where as speed does the opposite .. its easier to block if it does not have enough spin and the ball comes back faster so you have less time to react to the returning ball ...
Well, if you're thinking the only goal is to hit with more speed, I'd say Hit more by the "leggs" than with the arm. Put more emphasis on a full body stroke than hitting hard with just your arm. Be relaxed in the upper body but know how to "explode" with it. It's about energy transferring. Also combining this with a more flexible wrist (not holding the wrist tight, like I think you did in the video) will accelerate the shot, but more loose wrist will probably also make the shot less consistent. When you come through with those shots you should not be standing in the position you were before you hit the ball
All out shots, you know, like those Xu Xin does on "full commitment" shots.
When he basically rotates after/through the shot. I can dothat too, just that my consistency sucks compared to Xu. :v
It also works with Shakehand to a degree. Just that the wrist motion has less capability there.
If your goal is getting maximum speed, that's the way.
If you still need to go faster after pulling that off, faster equipment is only way.