FWIW C&C raised the boom a foot on the 30 Mark I in the middle of the production run (1972-1983), I believe 1978, as the original boom was a head-banger (I think I still have some dents...). The performance implications werren't considered material, no rating changes.
I'd say raise the boom. Go for max roach in a new main. If this is a roller-
furling boom, you might see if you can replace it with something longer, and switch to slab reefing.