The right amount of crazy instability work can bulletproof your shoulders.
Add some instability to your bench press by using a makeshift hanging band setup. (Alternately, do some dumbbell presses or push-ups on a Swiss ball.)
That kind of stuff can be the perfect supplement to all the other good stuff you're doing to promote healthy shoulders. Note that I said "supplement." That means it should make up no more than 10 percent of your routine.
Learning to control pressing loads that are unstable will light up the synergists to the major pressing muscles and help make them more responsive in general. The golden rule here is to practice pressing, but also challenge your pressing patterns – not with added weight, but with different tactics that make lighter weight feel more unstable or heavier.