Hmmmm, I wouldn't mind a Dell XPS 15. It's great that it has a non-glossy screen option.
I find the Unity desktop environment in recent Ubuntus to be easy to use right from the get-go, and unlike many desktop environments that run on Linux it doesn't seem ugly to me. Here's a screenshot of how I tend to work:
Windows can be dragged to the left/right/top/bottom to set them to use half. (It used to work for quarters in the corners, too - that's one thing I would like to reconfigure.) My launcher bar is on the left and is revealed when the pointer touches that edge as I find having icons visible all the time distracting, and this is a simple GUI config setting.
When was that, on what kind of hardware? I don't think that's a real problem these days, especially with Dells and other laptops being available which do support Linux.
I'm not into audio or video production myself, but in case you hadn't already seen them here a few bits of software I have in my list of interesting software that runs on Linux:
http://www.darktable.org/ (a brilliant RAW processor - this one I do use)