'Do well' is not enough detail for us to help you.
What conditions do you need your sheep to do well in?
Especially the climate, the topography (upland sheep won't appreciate spongy turf and lowland sheep don't climb as well and their hooves grow more slowly.)
What sort of management program do you have in mind?
Die Fledermaus does not fear such a tiny ad:
Switching from electric heat to a rocket mass heater reduces your carbon footprint as much as parking 7 cars