What about a possibility to define font in hint message's format string? For example, we define an array of special variables for font patch names (they point to 1st font patch), then we write a string format: centerprint("%font1%here goes some text in font one%font2%here goes text in font two"); or something like this.

Interesting idea.

It could be something similar to the ZDoom HudMessage specials <!-- s:) --><img src="{SMILIES_PATH}/icon_smile.gif" alt=":)" title="Smile" /><!-- s:) -->.

Yes, HudMessages should be used for this.