Well, my first suggestion would be dump KDE
Nah, seriously, you don't have to dump it, but it *is* a KDE problem; it is because of the QT underlying technologies that power up KDE; Those make it incompatible (well, sort of) with Gnome and it's GTK based core. The incompatibility is not quite all that big, since having a Browser basde on QT on Gnome works well and so does the opposite way; however, even though in Gnome KDE apps will look better that Gnome Apps in KDE, they pull out a lot of dependencies when they install. Don't know about Gnome in KDE but KDE in Gnome pulls out *all* of KDE except for KDM, Plasma and KDE-Session. Translated, it means that you almost have to install KDE in order to a KDE app to run in a non-KDE environment.
The problem is uncompatibility; if you really want a solution, I would Suggest the much more lightweight Xfce along with KDE in order to run a "non windowsifyed" (LOL) version of the app. If you don't like mixing DE's, you could always install another (Mint?) distro. Cinnamon has made the Main edition very usable. Anyway, let me know if you decide for any of the above (and if not, since you could, of course, just stay with that ugliness problem; it is not Ebola, is it?). I hope I have been of some help. Danko.
Cheer up! Things are getting worse at a slower rate.