We dont necessarily need a high power booster to power the LM back to
earth, its believed to be earth crossing, dock a small booster or even
a ion engine to get it back to earth.

Oh, so now you want to add an engine we don't have to all the other
nonexistent or imaginary things you've larded into your 'plan'.


Ion engines have already been used for deep space probes, at most it
might need to be scaled up, but could be used for other uses