I’m still in the test period, too, and am writing up a cohesive email to firstname.lastname@example.org that’s about equal parts feature request, support inquiry, and product review.
The fixed fontsize relationship and locked-in color are both particularly egregious when they’re so… not right. I can’t believe that anyone using OF wants their Folders in 24pt type, while I’m certain I’m not the only one who finds the greys of Darkmode a shade too dark. On the latter point, I can imagine that for older users or others with less than perfect vision this might be a real accessibility issue.
FWIW, the font size ratio seems to get a bit better if you increase size app-wide. Not ideal, but with all that space wasted anyway, doing so solves the grays issue, too. That ratio looks more like an intentional design decision.