in terms of music I think even iTunes is better than WMP10. The only problems with such players is that they try really hard to pimp their own formats (Apple pushing their m4a AAC and M$ their WMA) After that they don't offer too much support for any other formats which is why I tend to stick so ones that do. Winamp being the most popular I've found it has quite a bit of support and have stuck with it despite its faults using other players for their advantages.
My biggest grip with Winamp is that its separate parts might have been a good idea in a day and age where resolutions were high if you could run 1024x768, but now its just annoying having a separate box for a play list and a library, and while they're at it they just need to build the player into the the library/playlist (just like WMP10, real player, foobar, and iTunes).
It is true though, all the media players need to offer install options that offer the ability for users to select how much bloat they want/need.