Re. F-35B MTOW, does the phrase 'ski-jump' ring any bells ?
Sure it might have to be removable if minds were changed at some future stage ( though people like the Russians & their possible customers seem to fancy the idea with conventional jets too ) , but I reckon even I could design that, given enough plastic padding & some weight figures ( everyone stand at the stern ).
Of course the relatively difficult bit might be incorporating it into the aircraft software, but come on...