that's a good question. because i haven't yet been able to enter a rocket in god mode either.
I noticed that the god mode API in 2.0 is very limited and you are still just a player without a character (not like before in 1.1 in real god mode).
crafting/mining speed ist hardcodes, inventory size is hardcoded.. Wube never seems to have intended to fully implement it. (at least not yet)
to have the full functionality, i'm afraid I have to use the normal mode and hide the character. i'm still experimenting with it.