As the summary states, the new font is hardly legible with interface size "very small".
It seems like the outline of the letters leads to every letter fusing with the next, making it very hard to read (without major headaches). They seem to be more bold than before, which reduces legibility.
Either the outlining should be reduced depending on the interface size (or at least much more) or even a complete option to use different (ie. the old one) fonts.