I've always used relatively small fonts in my desktop environment, as seen in MyDesktopTour (although they aren't as small as the fonts some people I know use). This wasn't particularly because I liked small fonts; it's more because those were the font sizes I needed to use in order to fit two side by side 80-column xterm windows into a 1280x1024 display. I used them for years and generally didn't think about it; I mean, they worked and everything was fine.

(Looking at that shot of my desktop, the visible xterm is using my 'small' font, which I used for secondary xterms. An 80 column xterm using the normal font would be about as wide as the visible browser window.)

Recently I moved to a larger 1900x1200 display, which started a cascade of font-related changes in my environment. I am not going to try to describe them in detail, but the short version is that I eliminated my smaller xterm font size and switched the 'normal' font to one that gives an 80x24 xterm window that is about 12% wider and 19% taller than it used to be.

Perhaps my old fonts were perfectly readable as they were. But having made the switch, I will say that the new larger fonts definitely seem even more readable than the old ones. In fact, they make me feel that I probably was quietly straining my eyes a bit for years without really being conscious of it. Or to put it directly, there is a difference between readable and easily readable. A lot of text sizes are readable, even quite small ones. But you don't necessarily want to spend all your time reading text in those sizes even though you can. Bigger text sizes really are good for you in many cases.

(It's my opinion that this doesn't really change based on the display resolution, either. Small text is still small text even if it's rendered very smoothly.)

Hence my modest suggestion of increasing your text size, even if you think your current text size is perfectly fine and perfectly readable. You may discover that you were like me.

(I can't really do a true comparison of the readability of my old fonts against my new one for various reasons including that a true A/B comparison would have to have the old fonts on an old display, not the new one. I believe the displays are pretty close in DPI, but close is note quite the same thing as 'the same'.)