Shabbos davening in my shul averages 2 hours including the 10 – 15 minutes for the Rov’s drasha. We only recite a Mi Shehbeyrach for the “oleh aliya”.
One thing that can’t totally be controlled is “the leining is very slow”. A baal koreh can try to speed but if he is swallowing words or reading words baal peh to increase his speed nobody is yotzeh. I agree that some baalei kriah are “agonizingly slow”. However, I would like to give an analogy. You are driving and someone in the car is being a backseat driver: “slow down, speed up”. Do you listen or ignore it? As a bal koreh, I ignore such messages. I am in the driver’s seat and I can go as fast or as slow as I please, as long as the Rav and the gaboim are satisfied with my speed. One cannot lein the parsha like he his reading the names of the 10 sons of Haman.