Look into Moxie Collies. Several members here have collies from them. They produce rough and smooth. She breeds for conformation and has had BISS and group winning dogs, has several on working SD teams, herds, does rally, and used to do search and rescue until her partner's health problems prevented it.
She also does health testing on everyone. Jordan, her foundation bitch, got a hip rating of excellent on her OFA.
A lot of her dogs have a good amount of drive and work ethic, but they aren't hyper. I've found them to settle very well. Some are more laid back than others, so she may have a puppy who would be a good fit at some point. If not, she could probably direct you towards a breeder who does. I really like Colebrae collies as well. Colebrae doesn't do as much performance work, but they share a lot of the same pedigree as the Moxie collies.
I've helped her whelp and rear several litters. They are extremely well cared for and socialized.
Facebook page. There are lots of pics and health test results on it.
https://www.facebook.com/moxiecollies