Personally I usually fire up the player and go back to work, so I don't much care what it looks like, but I do have 2 thoughts:
1 - the IT curmudgeon in me would implore you to not add Java as a requirement to listen to The Amp Hour. Flash is basically ubiquitous (more so these days than java) and gets the job done just fine.
2 - The existing player is integrated into wordpress via the podpress plugin. I've never run a wordpress site, but I have to imagine this makes it very easy for Chris and/or Dave to publish content. Anything that goes against the grain of the podpress plugin's structure would likely create a tax on their already not-so-copious time. What you would want to do is skin the existing player. From what I can see, they are currently using the 1pixelout player (aka the Wordpress Audio Player) for The Amp Hour. AFAIK, this player supports themes (i.e. you can set the color of all the UI elements), but not skins. QUICK DISCLAIMER: I'm talking out my ass here since I've not done any of this. I think the path of least resistance to change the look of that player would be to use another player that integrates with podpress and also allows skins. The Xspf Jukebox
http://blog.lacymorrow.com/projects/xspf-jukebox/ seems to fit this bill. You can see some skin examples on that page, and they have docs on that site that tell you how to make a new skin.