I understand, but the fact is that BIAB always has bars of an equal length on a staff. PGMusic counts the leadin bar as a full bar regardless of the number of notes, so generally it takes up 1/5th of the staff (assuming you normally have 4 bars per staff).

I would also like notation to have short bars where appropriate. Consider the ending bars where there may only be 1 note over 2 bars. It's quite unnecessary to have that take up half a staff. The opposite is also true - a bar with lots of notes will look better if it's spaced properly.

BIAB is great, but it's notation could be much better. We have been waiting for better notation for a long time. 2004 brought us 'fake sheet' but not much since. Some new ways of entering notes, but printing has been pretty much stagnant

BIAB for Windows Version 2019 (643)
Windows 10 (1909)