Not to late at all
ive actually had this thread on my mind lately, but aside from setting up a few larger VMs to test games on i really cant think of what else to do. But i can answer ykur question a little...
GIMP reminds me of an older version of photoshop with atleast all the basic abilities and features. Im not photoshop literate beyond basic stuff though.
Ubuntu Studio is a distro Ive used a bit for audio editing and has a full compliment of tools for both audio and graphics. Check out ubuntustudio.org to see all of them. The default desktop environment is XFCE (i think), so lightweight and fast to respond. Full access to the Ubuntu Repos, but I am not certain what the package manager is (probably XFCE default).
Others that i have looked at recently that might strike your fancy are Fedora Design Suite and Apodio. I didnt spend long with either one but Apodio was set up out of the box to be reminiscent of a Mac (just in looks, it is still Linux/Ubuntu under the hood) and had a larger set of software pre-installed (both audio and video).
Beyond that GIMP is installable on every distro i can think of so you are free to pick from just about any one that you like. From my understanding, not much (if anything) is different under the hood of the custom audio/video distros except perhaps some fine tuning that I probably wouldnt understand.
Hopefully some others will chime in also, but be sure to post back if you have any other questions and ill give it the good old "college try"
