Xfce, by comparison, feels like each program is part of a package. That is not to say it's perfect: I still have to pull in Mate applications for things like a task manager, archive manager, and calculator. I also had to write my own replacements for things like a text editor that doesn't open every new document in a new window. But I get a whole lot of mileage out of Xfce's file browser, desktop, panel, terminal, settings panel, etc.
I'm a bit nervous about the Xfce move to GTK3, and I hope I won't end up with any client-side decorated windows, or the GTK3-style file picker.