Am I misunderstanding what exactly you are looking for? You can change the spacing in math mode of symbols/operators with https://typst.app/docs/reference/math/class/ and delimiter size with https://typst.app/docs/reference/math/lr#functions-lr (or automatically).

I didn't know about math classes, thank you for the reference

The issue I have with delimiters is that there is no option for "big", but only for "140%" or whatever, making it harder to be consistent Someone created an issue on this on GitHub if I remember correctly

And automatically chosen sizes are often too large

Good point! lr should support lengths in addition to ratios. Should be easy to add.

Ah, yeah fair enough! I was confused thinking that you were unaware of the existence of the functionality as a whole. Well, as laurmaedje (one of the main devs) said below, it should be easy to add, though it seems difficult to find which size values `big`, `bigg` and so on exactly represent.

It also seems to have problems with accessibility, based on this thread - https://github.com/typst/typst/issues/133

But then again, apparently so does LaTeX