Gmail Housekeeping

I just cleaned out my Gmail mailbox a bit. I went from 893 MB to 620 MB by deleting a bunch of messages that I sent with picture attachments. Usually when I send mail with large attachments, I like to keep it in my mailbox in case I need to access the attachment later, but after a while (like a few years later) I realize that I don't need them anymore, so I delete them for good. I guess in the future I could just send and delete from my Sent Mail box. Also, I guess I should look into archiving mail next so my inbox doesn't look so cluttered.