From the good points I would note the technical side. It wasn't that good actually, but for your first try you did amazing. I also liked how the characters played the instruments. I didn;t really like the idea itself, but it is admirable that you were able to do it.
From the bad points I would note the overall idea of the video. Characters playing on the instruments? Not bad! But showing some scenes form the anime was not that good of an idea, since everyone's already bored with those scenes, hence no emotions follow them. But simply characters playing for couple of minutes would also be boring, thus you should have questioned usage of this anime. From the technical point of view some part were done not very well, TV simulator was completely out of theme and all those media generated stuff also looked kinda cheap. But all those mistakes can be forgiven, since it;s your first try.
Overall, I can say it's not bad! I advice you to stick to AE. Seems to me that you care more about vertical side of the video, then horizontal. Which means that you pay more attention to image customization, then cutting. Well, so do I
And that's why I use AE! So, keep making AMVs! Nice job.
