My First impression was....too many Jumpbacks. My general feeling is everything on a reel should be your own work. The last thing you'll want is to be in a meeting with a potential employer and have to answer the question..."Now did you do that?" with... "No."
And if you did create the backgrounds, my apologies, but there are so many of them that there is no continuity to them.
Putting all of your work inside little boxes is tough to see and distracting. Go full frame with it. I think your work is of a good quality, but when Youtube compresses it (especially in the picture in pictures) you see some seriously bad compression. Since that is one aspect you are marketing, I'd get a high quality reel and post it somewhere outside of Youtube.
Basically since I've recently seen a lot of reels come in our office, there are two thing that really bother me and that's Jumpbacks and Youtube. Originality and quality are high points in getting hired, and editors should never skimp on those with their reels.
After 60 seconds, I still do not know what you do. Your backgrounds and small images are very distracting. I agree with the previous post, bring things up full frame, show the quality of your work. I don't have a problem with Jumpbacks, byt perhaps they are best used at the beginning and end...althought I would use something more subtle so your titles would stand out. On some of the clips how about letting the viewer hear the real audio?