The one that still tricks me even though I've played the map a ton of times is in King's Row in the end area, like near that U room with a large health pack before the last stretch, there's a fucking hole right there for no fucking reason. Not on the defense spawn side(though this one's annoying too but kinda makes sense with the shortcut up there) but on the other side. Like you fight people coming down the ramp from the street entrance in that area, and you strafe to dodge some shit and you just fucking fall down like a retard.
But yeah I like those, with Lucio, Roadhog and D-Va I knock people down pretty often. Volskaya Industries which wasn't available for the stress test has areas like this too but more limited, though you can knockback a bunch of people down right from their spawn point door if they don't see you standing above the door. Like it's a bit like Gibraltar side door, but even closer to the edge. Hollywood and the desert map don't have these. Hollywood is a lot more interesting than other maps though I find, it has a ton of verticality and a lot of building you can enter, there's often multiple windows and shit people can come out, it really emphasize the heroes with great mobility, I like it.