Definitely haven't ruled out labs or retrievers, they just don't seem to interest me although they tick every box activity/temperament wise. It's probably because most I've met have been allowed to get a little bit lazy & portly.
They do nothing for me either.
After having two collies for 15 years, we decided that we wanted a less demanding dog now. So we have two Cardigan Welsh Corgis.
I had criteria - no genetic issues (just keep the weight off them for back and leg health, but that would apply to most breeds); pastroral breed (although ours have no herding instinct); rare breed (on the KC Vulnerable breeds list and we have rare breed cattle and sheep); no slaver; no yapping (they do bark but it's a big dog bark, not like our neighbours' Jackapoo and miniature poodles) and a low maintenance coat (they shed but they have a double layered coat that shrugs off dirt and water, admitedly on to the floor. No trips to a groomer required).
They aren't small or fragile. Bryn weights 18kg; he's the same size body as our collies, just with short legs. Gwenna, his wee sister, is going to be smaller though.
Both (and their mother) have fantastic temperaments. They are pretty self contained, don't chase livestock, are affectionate, love everyone. Can cuddle on the sofa without having legs everywhere.
Everyone loves their own breed but I'd put in a definite recommendation for the Cardi. In tehse days of "fashionable" breeds and "designer" crosses, there's a lot to be said for these old fashioned, working breeds.