Thanks for the great model. I am going to print it right now. One tip for a future revision. You might want to thicken the support piece for the main body - the one that sits just below the engine. If one does want to scale your model down to 50% or less, then this piece becomes too thin to be sliced properly (with Cura 2.3.1 at least). If you were to make it as thick as the other pillar to the right of the rocket, then everything is fine.