Your "new" grouse gun doesn't have to be new to be a great grouser. I blundered into a killer deal for this well-used but tight and sound French Robust No.4 16 gauge. It was choked Mod/Full. At IC/IM the gun is the ultimate upland gun, IMO. It weighs right at 6 pounds and points like your finger.
You named some great choices in new guns, and I wouldn't mind having any of them. Don't overlook the old-school Classic upland shotguns.
a brace of big blues
a limit of two sagehen