I managed to clean up a few of the fonts I was trying out by selecting 'Remove kerning' when converting them to TTF using
Font Squirrel. This helped a lot, making the fonts much crisper on the Kindle.
One problem I keep running into, though, is that the terminal on the lower case 'f' is systematically chopped off whenever it appears at the end of a line. I've seen this now in five different fonts.
Changing the margins and justification doesn't seem to help either.
I've attached a screenshot here of Minion Pro Condensed.
Is anyone else running into this? Any ideas on how to fix it?