How do I limit caching in Mail for Mavericks?
With GMail, you can slightly aleivate this problem with:

Settings > Forwarding and POP/IMAP > Folder Size Limits > Limit IMAP folders to contain no more than this many messages = 1000

Also, in Mac Mail you can still disable Automatically download attachments.

This will leave you with the text of latest 1000 messages from each GMail label.