Well, Mate is Gnome 2, so technically… 
You pretty much downgraded your DE.
It’s like when I stopped using KDE+Dolphin for close to a year and switched to Cinnamon+Nemo because I thought that I needed to have KDE to use Dolphin. Ended up finding out I could use Dolphin inside Cinnamon without installing a DE I wouldn’t be using.
Or like yesterday, when I decided to test Index, PCManFM, Thunar, Nautilus, and Pantheon Files to see if they had enough features to compete with a simplified Dolphin or beefed up Cinnamon.
Long story short: THEY SUCK SO BAD. They are missing so many very basic things.