I am tempted to rent a car, check out the desert scenery on the way to La Pas and Cabo Pulmo, explore those destinations as well as Cabo San Lucas, and try their activities as well. It looks like lodging in Cabo Pulmo is scarce and the one place I looked at mentioned 90 square feet rooms - wow, shared bathroom & kitchen! I need to look further I am sure.
I think you could really enjoy that, just avoiding Cabo San Lucus altogether and focusing on San Jose, Pulmo and La Paz, those are quieter, sleepier, cheaper places pretty different from Cabo San Lucas. That inner portion of the peninsula is quiet and desolate, some smaller fishing hotels where serious fisherman travel from the US to go to experience the excellent fishing opportunities.