This sounds and feels very familiar, always loved Espresso and CSSEdit but also through changes in workflow strayed to Coda and also Codekit. I migrated further to Brackets and now Atom. Also used Textmate, Sublime text and BBEdit, but no other editor generates the amount of “feeling good emotions” as Espresso does.
Those MacRabbit guys did a remarkable job to bring Espresso up to modern standards, but looking back their UI standards we’re already pretty solid way back when they started.
At time of the release of Espresso 3, I couldn’t resist to try it and buy it again. Hopefully Dynamo gains the added functionality you’ve already mentioned, then I will certainly return to my favorite editor again.