Balanced staff spacing for staves of different sizes

Reasonably sure this one hasn’t come up before:
I have a score with optional trumpet and timpani parts which I have set to show at 75% staff size. This however results in an uneven distribution of the spacing, probably because the Vertical Spacing layout options apply to the space below a staff and are relative to the rastral size. There is no vertical pressure on this system and I have made no manual adjustments to the spacing. Could there be a way to distribute the reduced vertical space evenly on the top and bottom of the smaller staff, or alternatively, to have the layout options always be relative to a 100%-size staff?

edit: typo

I’m not sure it would always be optimal to have the gaps applied as if the staff were full-size, but I can certainly see that it would be helpful in this specific case. There’s no additional control available at the moment, but there could potentially be in the future (without actually promising it!).

Thanks for replying, Daniel. I suppose the problem will be a lot more complicated due to the fact that you can set a custom size independently for any staff, and the notion of “balance” will not be nearly as straightforward then…