Would be helpful if GpgOL would show a hint when the own key or that of the recipient will expire soon (in less than 7 days or something similar). Then you have more time to renew the key are create a new one and don't get into a situation where you have to write an email urgently but first have to manage you key. You are also able to remind others of the expiration of their keys.
On the screenshot you can see how it looks like in Kontact e35:
{F4703320}