DejaVu Sans - Ren'Py's default font.
It isn't default without a reason - it's just very easy to read.
"... for everyone".
Around there, there's people with a shitty screen, a extremely wide screen or a too small one. Some fonts are almost not readable when the size is reduced because the game resolution is higher than the screen one. Some other become unreadable when they are display at large size, and some are unreadable because of some glow effect on the screen.
There's also people near sighted, far sighted or astigmatic, when they don't have two or even the three because of their age. Of course they have glasses, but glasses don't reach a 100% correction, especially when there's more than one problem. For them, the letters will be deformed. Their brain learned with time to deal with this, but the letter must stay recognizable enough for this to happen.
There's also people who are color blind, red, blue, green, it depend. Your beautiful font look great for you, but once removed a color on the background they'll tend to merge with it. By default it's not such a problem. Like above their brain learned to deal with it, but here again the letters must stay recognizable enough.
And finally to this you must add people who have dyslexia and will be confused if some letters look too similar.
All of these people will play your game, and all of them should have the same facility to read what is wrote on it.
DejaVu is the default font for Ren'py since many years, and a widely used font on Ren'py games. If it wasn't a font which stay readable enough in all case, it would have been changed already.
It doesn't mean that you can't change the font, but that doing it isn't just a question of game customization. You can't just choose the font you love, you need to choose one that will stay readable whatever happen.
