I doubt there were any technical reasons to use Google Fonts. Designers use web fonts not because it is a technical requirement
As for caching: I don't get what the problem is. Google do cache their fonts in the way that allows them quickly fix problems with their CSS (if any happens).
Their
FAQs state that font files are cached for a year. Yes, they send an HTTP header that makes their CSS files to expire in a day, but these files are so small that this should not noticeable affect the page loading time. Plus it will be loaded once a day only.
What problem do you want to fix by switching from Google Fonts to "alternatives"? What alternatives would you suggest?