Speaking technically, I wish you'd kept one resolution [instead of having the need for black bars on the right/left sides at times]. It was distracting for me personally, but not a killing point of the AMV. There were also several watermarks I spotted now and again. Very few, but it's something to keep in mind.
Speaking in terms of content of the AMV, you hit the mood sync of the song pretty well. I was going "Awwwwwwwwwwwww... I want to give them hugs" throughout the whole video, and your cuts were pretty well done.
I couldn't help but feel that a few of the "lonlies" were less impacting than others [like Angelic Layer and Cardcaptor Sakura], and some of the overlays were a little hard to watch for me. Some of the "lonlies" were a little odd to see when out of a context. Staring at a sunset or just looking generally sad without any sort of reason/ryhme kind of made it odd at times. So I think there were some scene selection issues too.
Overall though, I think you did a pretty nice job with it. I notice that it's your first video uploaded to a-m-v.org, and I think you did pretty well especially keeping that fact in mind.
I definitively would reccomend a watch.
[Completely outside the review, I wanted to say that I didn't really dig the opening font and the raining sound at the very start, but that really didn't affect the way I reviewed the rest of the video]