Oooh. I think maybe you're uncertain about WHAT to have buyer's remorse about.
A pistol-grip-ONLY? Ok, you should lose that thing. Without experience to tell the difference, I'm sure it seems ok (I had one on a shotgun for years and know exactly how good they are) but it is a serious handicap even in tight quarters. It is movie prop nonsense. Until you get to a range and run some drills against a timer (lol, probably don't even need the timer to see the difference, but just to dive the point home...) you'll have to take our word for it. Or read our departed friend Dave McCracken's excellent treatise:
http://www.thehighroad.org/showthread.php?t=44465
Folks agreeing with your choice of a pistol grip were assuming you meant something like this:
Those can be useful, though on Mossberg 500 type guns they make the safety hard to reach.
PGOs sold to average folks are a pointlessly bad adaptation of something only useful for an extremely limited task in LEO and military settings (door breaching).
The side-saddle isn't a bad idea though a butt cuff is just about as good and does a better job of balancing the gun. (Once you get the right stock on it, of course.) Balance is important in a shotgun (though obviously there's no balance to a PGO). A white light is a fantastic idea as you MUST identify your target somehow and it is difficult to use a hand-held light with a long gun in your hands.
Oh, and every time you find yourself asking how cool or badass it looks? Slap yourself. Just a little. Then go buy another case of ammo and go practice SHOOTING it. If you aren't setting it up for optimal utility and then running it until the bluing's worn half off to make sure YOU can do the job, it isn't cool or badass. Just sort of a sad little false hope.
Hope that's helpful!