Let's focus on the last part, I think it's more interesting. > As I understand it, the disadvantages start once you want to put large payloads beyond orbit. St

Let's focus on the last part, I think it's more interesting. > As I understand it, the disadvantages start once you want to put large payloads beyond orbit. Starship's main goal is to put a payload on the moon (this is what the NASA funding is for) and for this purpose it is much worse than a traditional single use rocket: instead of a simple trip to the moon, the design is to launch to orbit, then do an additional 6 or so launches to refuel it while in orbit, and only then will it have enough power to fly to the moon. American plans to go to the Moon in 1960-s included a variant with LEO docking. That would allow using a smaller rocket, as the payload needed to go to the Moon could be assembled on low Earth orbit in several launches. NASA decided to go with one rocket of the size which was very ambitious at the time - about an order of magnitude bigger than the biggest existing one. The Starship goal is to bring even bigger payload to the Moon. Sure, it could be done by scaling up the Starship. But the fate of big rockets so far - Saturn-V, N-1, Energiya, even Space Shuttle to an extent - is that they suffer from the lack of use. The more they are used, the better and cheaper they get. So, no, the SpaceX goal isn't actually to bring even bigger payload to the Moon - it just happens that this scale, which Starship has, is good to land on the Moon a lot of payload in one launch. So, given that you want to use the Starship which is being created for many different missions, how would you use Starship to fly to the Moon? You'd refuel it on LEO. Noe we can remember the actual SpaceX goal - it's flying a lot of people and cargo to Mars, and SpaceX decided to create the biggest rocket they could reasonably plan, which is still not that large given that Mars wants thousands and thousands tons of stuff, so even this big rocket should be used with refueling on LEO. Once again - Starship is the biggest rocket SpaceX can build, from technical and economical standpoint (this reminds me the Soviet engineers chain of thoughts when they were planning N-1). It's still small enough for the task (flying to Mars), so LEO refueling is still needed. If it's still needed, it's logical to use it for Moon flights as well. Yes, instead of one flight (like Saturn-V) Starship needs several, for refueling. In exchange it brings larger payload to the Moon, so since we're planning to go there and stay, it could be justified. So, we're using a universal reusable super-heavy rocket for many different tasks instead of building a system for each task separately. We're losing in time - since we need multiple launches from Earth for single flight to the Moon - but gaining and payload and - crucially - in developing bespoke solutions for different tasks. I think overall it's an advantageous approach.