Oh so many
I've been trying to work out for about a year now what dog I want next, I want a BC soonish (probably before I get right into Kelpies as the DA thing, I'm still not ready for right yet) but the BC will either be rescue or working lines (after a few fosters so I know the breed more) and I also want to show, particularily GSP's.
It only occurred to me a couple of days ago that an Aus Shepherd might be an okay compromise, I don't mind the show lines and it would be a good introduction to a higher energy breed. So we'll see how things work out when I'm actually ready for another dog.
So my "one day" list is... in no particular order.
Kelpies (lots of them, they are "my" breed, just probably not my next dog because I want to avoid DA so I can get into agility with minimal fuss)
Border Collies
Koolies
Bullmastiff
Pug
Greater Swiss Mountain Dog (there are none int he country but I still have them on my list)
Australian Shepherd
Pug
AmStaff
Great Dane
German Shorthaired Pointer
Greyhounds (rescues)
I would oneday love a fila but BSL looks like its keeping them at bay