That's a purty shotgun, and if it's doing it for you, then it's doing it for you.
I've pretty much settled in on a CZ Redhead Premier Target, and I can get it for just a touch over a grand through the discount program, which is pretty solid for a $1500 MSRP gun. The trick is finding a LE/Mil dealer so I can take advantage of the discounted price.
I don't "have" to sell anything to offset the purchase of this, but the truth is, every time I go to the range, one gun I have that's a great gun, but I always seem to pass over, is my H&K USP 45. It just seems that whenever I'm looking to shoot a 45, I invariably grab one of my 1911s. I don't think I'd be sad to let it go. Maybe. I also have a Walther P99 that I never seem to shoot anymore, and I could probably be convinced to part with that one too.
So this is something else I discovered. I only thought I had the long barrel on my 870. It turns out that I had put the short barrel on it so that it was easier to store in the safe. The barrel I had on it was a 25.5 inch. I'd like to take it out again with the 30 inch barrel on it to see if I'd do better. IIRC, back with Dad I always shot better with that longer barrel.
CZs are great guns for the money. My BIL shoots a Redhead and loves it. It's a good choice for the money for sure. I use my shotguns for dual purposes, hunting and trap/skeet/sporting clays. I already have a TriStart Raptor for my sneak boat hunting on the Monocacy because I didn't want to worry about dumping one of my less replaceable classic Remingtons should I capsize. The same goes for an O/U in the field for pheasants. I can't (currently) justify north of $1k for a gun that's going to spend the day getting whacked by brush and crops and smeared with blood, mud, and feathers several times a year. Someday, I certainly will, but for now, cheap but reliable fits the bill.
I'm with you on the second part of your post. I keep asking myself "Why do I hold onto (this or that gun) when I haven't shot it or even looked at it in years?" I keep telling myself I'll trade them in at some point on a much nicer firearm, but I've yet to do so.
Regarding the longer barrel. I find that I do better with a 30" vs a 26" as there seems to be a smoother swing for me if that makes sense. It also balances better IMHO.