Another thing you may want to consider is moving your waist (but not your feet- that's illegal) like a mini body rotation. This may give your serve the small boost of power that it needs. I checked a few of your serves and this could be the missing piece.
Just watch any of the Japanese pro female singles player. They're small but they can serve very high. You have to first start with a side on stance and use some body rotation as PinkDawg mentions. Contact point is also to the side somewhere around the level of the mid thigh. Important to also use a loose grip so that finger power can be used. The hard part is probably a consistent strike at the sweetspot as you're probably experiencing, but this will come with practice as you find out where it's best to drop the shuttle to serve.
The forehand high service has a quite a fair bit of important things to pay attention to make it decent. 1. The swing to the shuttle cannot be too short, otherwise, you will need a strong wrist to flick it up high and far. After rewatching your video on a bigger screen, I could see that your swing to the shuttle is actually very short and you are relying a lot on your wrist to get it up high and far. On the other hand, your opponent doesn't really have this issue (he doesn't use a full swing, but still, the swing gives him an advantage), thus he was able to send it to the back and high enough. 2. Body rotation to generate power as others have mentioned. 3. Locking or bringing back of the wrist. Can't really tell from the video if your wrist is being brought back, but this small action will generate power upon impact, combined with body rotation and a proper swing. 4. Weight needs be on your racket foot. This is to kickstart the body rotation. As your body rotates, the weight shift from your racket foot to your non-racket foot. 5. The racket face or the racket angle should already be pointing upwards when swinging to hit the shuttle. A common mistake that some beginners make is that it either remains fairly flat, so the shuttle can't go really high. 6. Holding and dropping the shuttle. A small item, but again, plays quite a big part in hitting it proper. Don't really see any issues so far, but may need minor adjustments if you are adjusting for 2, 3, 4 and 5. 7. Following through. A very common mistake when serving high is not following through completely. Not following it through completely can result in a serve that's not far enough, not high enough or a combination of both. From your video, you have this problem. A video I like very much about forehand high service - http://www.youtube.com/watch?v=KsIxT9ddrf4 It has a slow motion view of the forehand high service, so you can really see the details to pay attention to. To have decent footwork, it needs to be practised on a regular basis. Additionally, you need other exercises to improve the explosiveness and agility of your legs to improve your footwork. From your video, you know the footwork, so now that's not the issue. What might be lacking is the exercises to improve the explosiveness and agility of your legs. You also appear to be quite rooted to a position after playing a shot, that's why you can't recover fast enough and is always rushing to various ends of the court. The exercises may help. Not meaning to be offensive, but I have my doubts... As you play in this gym regularly, you should be quite aware of the lines by now. Do you stroke for a while using half a court (straight clears) and full court (cross court clears) before starting a game? How far are you able to clear for straight clears? And from which area of the court? Stroking is not just for warming up the body, it's also to adjust to the conditions of the court, to be aware of how much strength you need to put in to hit the shots to a desired location. [HR][/HR] Other issues I noticed after I rewatched. 1. Your forehand clears have a tendency to max out after a certain distance because you are taking the shots squarely and hitting with all your strength. Similar to forehand high service, you need to adopt a side stance and apply body rotation to generate power so that it can travel further. 2. Your forehand smashes aren't really going down, although they do have a fair bit of power and speed in it. Similar to your forehand clears, you need a side stance and body rotation to generate power. If I am not mistaken, your forehand smash technique isn't quite right, so your smashes will not really go down most of the time. A video that may help since it breaks down the smashing technique - http://www.youtube.com/watch?v=oWlKBvHaP2k There are several smashing techniques, but this is one of the most common. 3. You are standing fairly tall and are fairly rooted to the ground. This will affect judgement and ability to move around the courts fast. 4. Your non-racket hand isn't really put to use, especially in forecourt play. If you need to move around fast around the forecourt. The non-racket hand can help you. 5. You sometimes do not prepare your racket (racket is not out and facing correctly) for forecourt soft shots. So you need to take an extra step and the returned shots may be awkward.
