Hello there
A couple of little things I do (sorry if you're already doing this!):
1. The oven must be up to temperature when they go in
2. Aside from rubbing in the butter, mix them as little as possible
3. Knead them as little as possible
4. Try gently using the palm of your hand rather than a rolling pin to flatten the dough
5. Cut them thicker
6. Get them into the oven as quickly as possible from the time the liquids hit the flour
No matter what scones look like, they always taste so good!!