[jccooper]

Starship itself will not be a great deep space delivery vehicle, in the same way current disposable second stages are used. Too big and too... reusable.

However, it'll make a great delivery system for some serious high-energy escape velocity "third" stages, rather like the Shuttle "Inertial Upper Stage" that delivered Magellan and Galileo and Ulysses.

[Laremere]

Well, Starship is specifically designed to make it to Mars if refueled in LEO. So it could deliver monstrously large Mars rovers. If they're going for the outer planets, they could do as you suggest after the first burn using a refueled Starship. Either way you're sacrificing a Starship second stage (old, or better yet reduced mass version) to the gods of delta V.

[jessriedel]

A re-fueled Starship will be able to deliver ~100 tons to the surface of Mars, to be compared with the heaviest existing rover that was slightly over 1 ton. Yes, it will take ~10 Starship flights to fully refuel one Mars-bound Starship, but the fully reusable design is supposed to ensure this can be done for relative cheap.