JTO,
Good link here to an February this year setting out the Japanese approach to the Izumo design.
Officials Admit Japan's 'Helicopter Destroyers' Were Also Designed For Jets - The Drive
Looks like they took a sensible approach to sizing of lifts, deck strength, hangar deck head clearance, aviation fuel capacity etc. If they got these about right, getting F-35B on board will, be a simpler job. Putting the ski jump on would be an extremely smart move.
Best Regards as ever to those taking the tough decisions,
Engines