STOBAR would be a good idea, regardless. A lighter weight arresting system would be cheaper, but couldn’t trap F-35s. But it would allow the RN to do what Brazil is doing and refit old C-1s and S-2s (which used to launch via deck runs a lot, even from Essex-class CVSes) for COD and tanking duties. Even as an alternative to the Merlin based Sea King AEW replacement.
From what I understand, when the Royal Navy was dithering back and forth between CATOBAR and STOVL for the Queen Elizabeth, the limiting factor was the cost of retrofitting an unproven EMALS system into a ship already under construction.
Being an ignorant former enlisted blue-suiter, it would be my guess that retrofitting arresting gear wouldn’t be quite as involved as the catapulting gear.
Wouldn’t a COD be operating at a higher landing weight than an F-35C?