So close to 600k.
Second best strategy I have found for this game is to repeatedly bump into the x4 and x8 platforms to get the 4k and 8k bonuses, then land on an x8 platform without using the landing legs, use z to burn out the rest of the fuel for an extra bonus, then deploy the landing legs.
First best I guess would be to land on the starting platform and wobble for infinite points lol