Simon,

What version of Squeak are you using?

I know I can choose my own size using StrikeFont class>>fromUser, but what's the best way to do this in my code, non-interactively?

This is a good starting point. StrikeFont class>fromUser calls: StrikeFont class>fromUser:allowKeyboard:, and down in the method, you find lines like:

ptMenu add: 'new size' target ... #addNewFontSizeDialog: ...

This suggests that for the 'new size' menu item, a message whose selector is addNewFontSizeDialog: is sent to an object. And if you look at the implementors of the method, it is TextStyle.

So, if you evaluate:

(TextStyle named: 'BitstreamVeraSans') addNewFontSize: 120.

you can add the new size.

Oh, and should I prefer TTCFont or StrikeFont, or does it not matter?

StrikeFont is pixel font and not good for making new size programatically. Your safe bet is on TTCFont.

And what should I use for the font family, for maximum portability? Can I assume BitstreamVeraSans is always available? What's better than assuming that?

Nobody would lobby to remove it but you could do:

TTFontDescription default name

to figure out the "default TrueType font" in the current system.

-- Yoshiki