Congratulations for starting your own publication, Rachel! :)
I was thinking a bit more of your third point in this article. My very first articles on Medium were related to the crap I was taking as a freelancer!
One mistake I made was using a "swing for the fences" approach to freelancing where I'd do a lot of bidding for six-figure contracts in the hope of scoring a huge deal. This approach sounded great on paper, but it gradually dawned on me that
"The amount of crap is directly proportional to the contract size"
which is a nicer way of saying "the more people pay you, the more crap they're going to shovel at you"
That's why I'm going for a larger quantity of smaller-ticket clients these days!