I do not have a solid solution for your older e-mails but a concrete one for your future ones.
You mention:
However, it also (undesirably) prevents it from matching incoming
messages that I send to myself or that someone else has sent to me
“from” my own address. Is there a way to only exclude my own outgoing
messages?
For future e-mails
We will reverse the whole idea. Instead of excluding your own outgoing messages you can create a new address you will be using to send e-mails to yourself. Even better you can have friends send or anyone else to it as well.
We can do that because Gmail will not acknowledge periods as characters in addresses.
Example:
Let us say your Gmail account is under myname@gmail.com
.
- An e-mail like
my.name@gmail.com
will still come to the same inbox.
- The same as
my.na.me@gmail.com
- Or
m.y.name@gmail.com
- Even
m.y.n.a.m.e.@gmail.com
Starting now, you can e-mail yourself to my.name@gmail.com
or have someone else send an e-mail to you “from” your own address. Filter, star, label these messages with ease. You can find more information about using dots in Gmail addresses here.
As for older messages, find them (or whenever you come across one) and forward them to your new address. Your corresponding filters will be automatically applied to them as well.
Note
Some people may get confused by using dots in the e-mails. If this is the case please use a different approach to a possible solution for your issue described here.