I'd like specifics. Is it pacing? Variety? Creativity? All of the above? Also...what's the best method if you have multiple skills (Videographer, Editor, MoGraph Arist)? Should you make a reel tailored to one particular skill, or create one that showcases all of them (thus, making you appear more versatile.)?
Rob, you ask a very good question, that probably has as many responses as there are cow members. I am for an editor, that does direct, shoot and do a couple of other things, but a damn good editor none the less.
I edit and design many different projects that range from high end national commercials, to news/VNR pieces, corporate and documentaries. On multiple platforms and software. I cover a broad range of editorial and I try to have my demo reflect that in a short opening montage and then expound upon the subject material that I feel would best be suited for that particular client or job.
If you are posting a reel for the web, then maybe you add the other things that you want people to know that you do. I would suggest that you add some sort of heading or graphic to denote what you are showcasing.