The pit sticking happens with immature fruit in my experience. The fruit falling is likely due to the heat wave primarily, I'd guess. I think you're right on those two guesses.
I'm near you in Ramona, and while my Hass hasn't dropped any fruit, my Reed dropped a couple last week. Neither of those trees is shedding many leaves right now, but my Lamb shed many leaves this time of year in its first three years. I'd bet your Hass will do less of both the shedding of fruit and shedding of leaves this time of year (bloom time) as it gets older.