Hey guys, I have been playing with font combos in my theme. I took this formula form Pop!_OS and it really does make a nice change to readability and the look of everything. I thought it may be something worth considering that would be fairly easy to change and may make a big difference in appearance of the distro in general.
Window Titles: Fira Sans SemiBold 10
Interface: Fira Sans Book 10
Documents: Roboto Slab Regular 11
Monospace: Fira Mono Regular 11