As mentioned in this thread about the recent font size increase, I have found that I prefer the old base font size of 15px to the new one of 16px (in particular because of the size of thread titles, which is 18.4px on my Desktop). Unfortunately, the current font settings are relatively coarse-grained and only allow me to step down the base size to 14px. Thus my request would be to allow a more granular control of the base font size. I don't necessarily need specific pixel sizes (though that might help, too) - a slider from small to large that effectively has 1px steps would be equally fine.
Discuss this on our forum.