Not into the shiny finish on the stock and forearm. Needs a flashlight, front sight, extra ammo holder and Choate shell follower in the mag tube. An extended mag tube would be another option along with a sling and large button-head safety.
I agree with the BBE's sight comment. Along with adding a good light (I like Streamlight TLR-1's).
You may also want to consider shortening the stock an inch or so and upgrading the recoil pad (I like Remington Super Cell). The shorter LOP makes a significant difference in the 'handiness' of the shotgun. With your wooden stock, it's a pretty easy modification to make.
Take it to the range with a stack of clean cardboard and pattern it with the various brands of ammo you intend to run, at representative distances. It's critical to fully understand how your SG works with your ammo (it can vary wildly).
Agree with Huntall50+ Good add ons, practical and inexpensive. Simple seems to work well without all the tacticool "do dads."
The clip on Hi Viz works well with a dab of silicone, no movement. Installed one 4yrs ago, still in place, no issues. (On my H&R Single shot 12 ga "Deer Thumper").
Good find.