Building in this game is hardly simple... also a death star would be in space so it would make more sense to float around than use scaffolding.
I don't want it to be simple, i don't think adding a tedious babysit mechanic adds to game play in a meaningful way. Also when building ships and what not you will have to take into account aerodynamics, weight, fuel capacity, etc. There will also be scripting.
I would say the building is much more complex than minecraft level of simplicity, in mine craft its grab block place block.
Like I said before if you want to forgo using the jetpack and want to make scaffolding you can do that with the jetpack the way it is. If you think it's fun to play that way you can do it without affecting everyones gameplay.
This is the difference between the 2, with your way you force everyone else to play your way without giving us the option to play the way we like. where as with the jetpack the way it is you are still able to play in a restricted manner if that indeed how you'd like to play. Nothing is stopping you and your friends from building scaffolding for immersion purposes.