what if i told you X applications can see other X applications, that one application's crash/freeze can affect the entire OS interface when using X, that most distros default to not securing/hardening the kernel, that wayland needs to be a priority for everyone yet it seems only red hat focuses on it (at the same time red hat focuses on systemd that so many people hate), that ubuntu sloppily tries to do things on their own out of spite instead of using/collaborating with standards, that long term releases can get really annoying if you want to run new hardware or software as they arbitrarily stay on old versions (i'm saying maybe you could have gone with 16.10 instead of 16.04, though 17 is about to release, not that it matters, feel free to upgrade)
waro, i assume you know what i'm talking about
anyway, kodi is great but isnt it fullscreen? it's also multiplatform so not linux specific (well, same for vlc)
surely you have preferences in your software, for example maybe you want a simple audio player not a giant library manager, maybe you want your video player to open as fast as possible, etc... so the best player is one you choose after trying several out (again not linux specific, unless you are one to use default windows players)
i'm unclear if you want to play multimedia or produce it, but if you love adobe's workflow then you might have a problem
i'm going to mention that solus (with budgie, not mate) looks like an exciting distro that looks good, doesnt get in the way, & lets you install steam or other proprietary apps, i would try that rather than ubuntu