I should be in bed, but I'm not. Instead let me draw your attention to the fact that the statusbar (in Caja and Eye of MATE for example) doesn't respect the GTK font size setting.
This is annoying because the statusbar displays important information, but the text is very small. It also goes against the "GTK tradition" of having one font size for menubar, toolbar and statusbar.
Good night and thank you for working on MATE!