not GP either, but I did the same and migrated to Fastmail. The transition was extremely smooth, and at least for now gmail allows you to set up integration (either forwarding rule or remote retrieval through IMAP) to forward you old e-mail to fastmail. I have it set up to auto tag all incoming gmail mail and move it into a folder that I check occasionally to see if anything interesting came through.
One amazing advantage to using fastmail (or really any real e-mail provider) is that it is trivial to set it up to use your own domain for e-mail, and to do catchall addresses for your domain. I use this feature heavily, using the general strategy of giving every service a different e-mail address. In this way I can sort by incoming to field, and block out anyone who sends spam using rules acting on the to field. This does an amazing job of sorting out things like mailing lists that keep re-adding you or that are worth monitoring but aren't worthy of showing up in my inbox.
One amazing advantage to using fastmail (or really any real e-mail provider) is that it is trivial to set it up to use your own domain for e-mail, and to do catchall addresses for your domain. I use this feature heavily, using the general strategy of giving every service a different e-mail address. In this way I can sort by incoming to field, and block out anyone who sends spam using rules acting on the to field. This does an amazing job of sorting out things like mailing lists that keep re-adding you or that are worth monitoring but aren't worthy of showing up in my inbox.