I thought folks might be interested in seeing those same 2 baby Echinacea plants this year.
As you can see, they don't appear to have suffered at all! They are waist high, "full and fluffy" (to quote Barbie), and covered with dozens of blooms.
Interestingly, I've planted several more young Echinaceas in the new half of the flower bed...and they are currently covered with checkerspot caterpillars as I write. The older, "more experienced" plants that dealt with them last year seem to have escaped becoming larva food this year. It makes me wonder if the adult checkerspot females preferentially seek out young plants to lay eggs on, or if the young (newly transplanted) plants are sending out distress signals until they get established...or if this was simply coincidence.
I'll probably never know, but it's interesting to hypothesize and try to figure out what makes sense.