While I haven't had to edit in that environment, I did work various cubicle jobs in my early 20s, one with half sized walls and the other with these weird open zig zag tables.

1) Check out semi-open-back headphones like the AKG240s. They go fully over the ear and they breathe which is nice. They're cheap, have a good reputation for studio use, and do allow some ambient sound to come in. A good alternative to the standard Sony 7506 which rest uncomfortably on the ear.

2) Get a monitor hood. This should decrease lookie-loos, will reduce people reaching in and touching the screen, and you can easily bullshit an ergonomic excuse like eye fatigue from the overhead lights.

3) Get a decent laser pointer. Clients and co-workers can use it to point on the screen instead of touching it.

4) You just gotta train your coworkers. Producers, of course you have to acquiesces, but just throw up your index finger "one moment" when you're tapped on the shoulder by a coworker or let them know after you answer their request that you would appreciate it if they could keep the interruptions to a minimum. You just gotta work your way up to the person in the office who isn't infinitely interruptible.