under Kindle "Debricking Repair" Images one can now find a link to Paperwhite image with the name pw_5.2.0-mmcblk0p1.img.gz.
Using explore2fs one can see that /usr/java/lib/fonts/ is empty. But there is a file name fonts.cramfs.img in /usr/java/lib/
Extract it and then use 7-zip to extract it (WinRAR can not extract it). And you now have a list of new fonts to choose from (Baskerville, Futura etc.)
And Caecilia is at version 6.01 or 6.02 in the PW.
Use the same procedure to upade as before. To get the new fonts in use make a file named USE_ALT_FONTS in kindle usb drive root and use the ";fc-cache" command. After a few minutes when the new fonts can be selected when in font size selection.
So happy new fonts!
Edit: and here is a comparison between k3/k4 newest Caecilia vs Paperwhite
Clearly more contrast but other than that this is not as great leap forwards as going from stock K5 to K3/K4 latest (many changes in letters etc).