50/50 is "shooting flat". You said that it seemed to print a bit more than 50% under POA. That's not good. I love a gun that shoots 60/40 (60% of the pattern above the POA). For my shooting style that works very, very well. I refuse to shoot a gun that patterns higher than 70/30, which would require "floating the bird" above the muzzle to some degree. That is not good for consistently good shooting either, as the amount you have to float it changes as the distance to the bird changes. Please keep in mind that I am excluding the game of trap from this conversation, in which a "built in lead" is desired by most, as the birds are all rising.
The simplest solution to make it pattern a little higher is to build up the comb a bit, where your cheek contacts the comb (DAC). That is very easy to do with moleskin, which can be layered to build it up incrementally.
What ed good suggested may actually work, as it lessens the leverage against the gun's muzzle flip. However, I don't like the idea of making myself to fit the gun. . . . much better to make the gun to fit me. When you have to remember to grip this gun here, and the next gun there, it's just not a good recipe for sustainable success with a shotgun .
Richard Hale's first reply above is excellent, and very well said, with much truth.