Here is a creative solution I have just started using. I created labels sent2016, sent2015, sent2014, etc. Then I applied the labels, for example search for sent emails before:2016/01/01 after:2014/12/31, select all, then click on "Select all messages that match this search", then apply the label "sent2015". After doing this for each completed year, I then labeled all the current year's sent messages too (sent2016).

The next step, for me, since I read my email in Thunderbird, was to unsubscribe the Sent folder, and to subscribe to sent2016 instead. Now when I look at messages in sent2016, I'm only looking at the current year, not 8 years worth of messages!

I think this would also be somewhat helpful if I were reading my gmail in the browser, too, because instead of checking the "Sent" box, I could look in the "sent2016" label.

(I did select all the old sent messages labeled "sent2015", for example, and hit "archive"; but I don't know that that was particularly helpful....)

Here is a creative solution I have just started using. I created labels sent2016, sent2015, sent2014, etc. Then I applied the labels, for example search for sent emails before:2016/01/01 after:2014/12/31, select all, then click on "Select all messages that match this search", then apply the label "sent2015". After doing this for each completed year, I then labeled all the current year's sent messages too (sent2016).

The next step, for me, since I read my email in Thunderbird, was to unsubscribe the Sent folder, and to subscribe to sent2016 instead. Now when I look at messages in sent2016, I'm only looking at the current year, not 8 years worth of messages!

I think this would also be somewhat helpful if I were reading my gmail in the browser, too, because instead of checking the "Sent" box, I could look in the "sent2016" label.

(I did select all the old sent messages labeled "sent2015", for example, and hit "archive"; but I don't know that that was particularly helpful....)

P.S. I also unchecked IMAP for the old labels.