I use 1 principal account.
Then i add external ones or personas.
I forward my emails from other accounts (gmail or different).
I organize my email in folders and tags.
But there isn't the possibility to see ALL the email i receive in a unified inbox.
I always have to check the single folders and this is very frustrating...
Would be nice to have a "smart inbox folder" in whic i can see all the emails i have received, being possible to see all the unread, to see in which folders they stay, at which account they refer to... and so on...