Loss of font option in colour themes (previously schemas)

Hi,

I'm sure I'm not the only person to be seriously frustrated that the
new colour themes don't allow font settings the way that the old
schemas did.

Specifically, I want to be able to work with proportionally spaced
fonts generally, but need mono fonts for specific purposes at some
times. Previously, I could just set the appropriate editor pane to a
'monospace' schema when I wanted this, without affecting any other
contexts.

Is there an alternative way of achieving this functionality, or is
it planned to be restored?

TIA.

Steve Rencontre.