The new version of
Software Boutique (v2.0) will be become a software centre
That's great news! It'll be very usefull for new/non-tech users.
I like some green 
I started with changing the wallpaper 
My understanding are technical limitations with "fractional scaling" which would provide scaling between 1x and 2x, like 1.5x.
It is experimental and a shared problem across a few desktop environments, and really something that will be solved when future technologies like Wayland become more prominent.
It is a similar problem in a lot of distro's. In Ubuntu it's possible to switch to 1.25, 1.50 and 1.75 scaling too. It's something to look forward too
I'd like to add another positive impressions:
- The standard workflow in Ubuntu Mate is a lot more logical than in Ubuntu (Gnome). In Ubuntu I had to install extensions to make it fit my expectations of a desktop.