(...then the obligatory but)
I really did enjoy the simplicity of the setup... Set the size of the player in the setup area, put the ids of the videos you want in the short code, and vuala; you're done. (Including an example of the needed short code in the setup area would be a nice touch)
The player is clean and has a nice look. I like that the videos in the playlist are clearly below the player rather than being embedded in the viewer as is the case with a YouTube playlist.
Okay, you knew this was coming...
You have set the videos on the playlist as anchor links to the top of the player, which means that the page jumps to the player when any video is clicked on. This effect did not work for me. To have the page jump when a video is clicked is somewhat uncomfortable when one is not expecting it. On my setup it took the top of the page about 10 to 20px below the top of the player, which meant I needed to drag the page back up to see the entire screen.
It would be nice if a smoother way to move through the playlist could be developed rather than needing to drag a scroll bar.
It would be nice if the currently playing video could be highlighted in some way (now I'm nitpicking).
On a more practical note, being flash based, this is useless for mobile use; and responsive design is needed as well (sorry, those are just the facts in the emerging mobile future of the web).
I appreciate the time you have spent, zykhan, in developing this plugin and thank you for your effort. I highly recommend it for anyone looking for a player with playlist, that is easy to setup, looks good, and works well in a desktop environment (if that anchor thing is worked out).