Taking 4 days after Oakhurst wedding--interested in missions, a beach day, history--less travelled spots but only short hikes
Monterey and Carmel fits your criteria. There are plenty of less explored, off the beaten path type hikes that you can visit locally. And, even in July, it won't be too hot. It will just be a bit expensive for the hotel, but that's going to be the case anywhere on the coast. Book accommodations soon.