Bold Sans fonts are extremely wide in Hebrew. a bold Hebrew Sans string is approximately 20% longer (!) then an identical non-bold string. This not only interrupts with proper reading, but also distorts any websites using bold fonts (example: www.haaretz.co.il, note the blue links-bar below the title and the titles of the individual stories). I have mentioned this earlier several times in letters to the mailing list, but to no avail.
This problem does not exist in any other common font used for general display of Hebrew (Nachliely, Guttman, the MS family...). It does not exist in Latin letters used in DEjaVu sans, where the difference in length between a bold and a regular string is only about 5%, which is much more bearable.
Created attachment 15454 [details]
Narrower Hebrew characters in Bold
This is a test wit some narrower Hebrew characters in Bold. Not all characters have bee modified, for example ש <U+05E9> since it needs to be wide enough for compositions like שּ <U+FB49>.
Very nice work! It looks much better already. The work on ב, כ, ך and ק is especially noticeable and impressive. The spacing also seems to have improved greatly.
If you want to try and squeeze it a bit more, I think that ך and maybe ד can take some more narrowing. The letter ש, as you noted, is still problematic. I think it should not pose a difficulty, because bold font is very seldom used with diacritics. Hebrew diacritics are used in dictionaries, poetry, religious texts and children's literature, but not in titles. Also, in some fonts the diacritics in the ש are only partially seen (the dot touches the middle "pillar"), and this is perfectly fine.
Thank you for the good work!