Engines is correct. Ski-jump is synergistic with STOVL - partly because of powered lift and partly because a STOVL aircraft has not only lift, but also control below its wingborne flying speed.
But to get back to the "bin lid" point: A Harrier-type STO has a certain elegance in that you start the roll with 100 per cent thrust straight aft and can then quickly and smoothly dial in any amount of vectoring. The F-35 is a bit more restrictive in that the aft nozzle is delivering part thrust for acceleration (because the lift fan and roll posts are active), the lift fan vectors to 45 deg only and the roll posts (9000 lb thrust) do not vector aft at all.
Luckily the F135 is a
ing big engine...