I don't have many firearm accessories firm believer in KISS
Like my safariland paddle holsters- they don't sag, and I have a 5" XD 45 and my wife a M&P 9 full size. Do like my loaders, one for the pistol mags and the mag charger adapter for my 308 stripper clips. got one for my civvie AK long barreled clone. Have a circle and dot sight for the AK, great for feral hogs in the creek bottom. All my 308 rifles have mil-dot scopes, again good for snap shots as they eliminate the need to dial in for any distance under 600 yards. They are second or rear focal plane which means they can be used at half power for a bigger FOV and capable of large leads on hard running hogs out in the open.
Have a older Leica LRF, good but not great. Works well enough on game out to 500 yards and steel targets out to 800 depending on the brush around it. Have a cheap Caldwell wind-o-meter, just need approx wind speed these days and out to 400 yards unless the wind is full value it isn't a huge factor under 10 mph. Oh have short and mid height bipods for my 308s. They are 'rockers' with locks.
Have an old tripod with a PVC pipe trough attached. lined with foam that has been sprayed with plasti-grip. Good for tall grass brush work- don't use it much but do like to practice with it.
Have a nice, again older, Nixon spotter scope- good for spotting hits on steel out to 1000 yards, ballistic trace on the UNK distance steel ranges and mirage for wind calls.
I have several shooting jackets with the 'sissy' pad up high, over the collar bone and top of shoulder for prone work. Students and guests get kidney shaped pieces of foam sleeping mat pad that get tacked inside their shirt with some tacky spray like for headliners.
As a comfort thing I have mic earmuffs with a speaker jack plug-in. Like my music while I practice. Like being able to talk to and hear those I bring to the range to show how much fun marksmanship can be.
Have a repair kit with a compact screwdriver type torque wrench, allen and star drive wrenches for scope mounts, lens pen to keep dirt out with minimum lens scratches. A fold up shooting mat that fits to the ruck I use for rifle range gear.
Guess that's pretty much it... just the basics for shooting...

eace