I haven't used KDE for 10 years or so, but what makes you prefer that over a tiling wm? Considering you were already there, the learning curve must be zero, and nobody is forcing you to spend any time modifying anything. It kind of just works. At least it does for me.
There are a very few things that I will drop into Gnome to do (I think it's Gnome at least), and I dread it every time. Too many menus everywhere, too much animation, tiny targets that I need to hit with the mouse, etc.
KDE5 is super nice and doesn't resemble the horrors of KDEs past, at least in my opinion, you should give it a try after all this time to see all the great work they've done since you last saw it.
There are a very few things that I will drop into Gnome to do (I think it's Gnome at least), and I dread it every time. Too many menus everywhere, too much animation, tiny targets that I need to hit with the mouse, etc.