When replying to a conversation that I have already replied to, it should reply to the other party, not send the email to myself.
If there is a conversation between me and another contact, if I receive an email from the contact and then hit reply, it sends the email to them. If I hit reply again in the same conversation so send another email before they answer, it now sends the message to myself, not the other person. That is utterly pointless. Make it so that it always replies to the other person or people, like in Gmail.