My Surface Pro 1 handled a large galaxy just fine. I tried an insane sized galaxy the other day on my Surface Pro 3, and I had to dial it back to 'low' graphics settings, and it was still kinda laggy/jumpy. I expect that it should have enough meat before it's all said and done. The SP3 is an I5-8g Ram model.
@Frogboy: Yes. And the situation is exacerbated by the fact that the surface pro 3 doesn't have a mouse button for the track pad, and the middle mouse wheel on the Arc Mouse doesn't function as a mouse button either. I have to plug in a clunky mouse in order to play the game :C