I would find it very useful to have the message rule names alphabetized in the rules dialog.
I have over three hundred rules defined and when I need to modify one, I usually end up just giving up finding the one I want to modify, and close the dialog.
Also, in the rule definition dialog, the addition of a new condition called 'from contains" would be very useful. A string would be entered which, if found anywhere in the from address, the rule would match.
I have several messages coming in with different usernames with the same “from” domain. With this change they could all be processed with one rule.
I find eM Client a really good product overall.