@NiLuJe: I am trying to replace Palatino with CharisSIL. I have read your post #92 but when I try that, namely in my case:
start with fc-override.tpl, tweak it : TO_OVERRIDE = Palatino; TO_USE = CharisSIL, and save it to linkfonts/etc/conf.d/98-override-Palatino.conf
Palatino gets replaced by Helvetica (although I did write CharisSIL as a replacement in the scrip).
Now if I try to replace the serif default (bookerly) with CharisSil by just using the hack, without manually tweaking a script, that works perfectly well, so CharisSIL seems to be ok.
Is Helvetica the Fallback font, and what am I doing wrong?
I'd love to also replace Futura with Trebuchet. I know you are advising to not replace the sans fonts, but would Futura be less problematic than Helevetica ? Because I never ever ever use Palatino, Futura or Baskerville and it would be great for me to be able to replace them.
PS: I know the font hacks is not your favorite child, but I would really appreciate your help here.