I've looked at quite a few reels in the past months. There have been discussions here on what casting directors and agents look for. The general consensus is the following -
Keep it simple. Show off your talent and nothing else.
The music in these take away from everything. The lengths are KILLER. Even if I liked the songs I still wouldn't make it through the entire thing.
As a quick example in the Linkin Park (ew alone): What does the first minute show of your talent? The first thing that shows anything for more then a split second is when you're ripping the photos off the line.
A reel should be no more then 2 minutes, and show as varied amount of characterizations as possible.
Think of it this way: If someone is searching for an actor, they don't have 5 minutes to watch a single video. They want to see TALENT from the get go.
I once went into Island Records for a meeting with A&R. The guy listened to maybe 5 seconds of two songs, and about a minute or so of the third. He told me to bring him back a finished master of the third. I never did. But, what could he possibly hear in 5 seconds of the first two? It doesn't matter, because he was in charge.
2 minutes, simple, no extra music, no photos. That's what they want. Give it to them.