I've always been pretty happy with the old style ZyXel GUI. It's easy enough to use and generally reasonably responsive. Why they decided to update it a few years ago I do not know as the new one just seems harder to use to me, but then I'm generally a 'if it ain't broke don't fix it' type of person.
I did have a Netgear some years ago and the GUI on that was ok too, unlike Technicolor whose GUIs, in my experience, are awkward and sluggish.