Welcome to Mossberg Owners!
If it's something you may need in the dark, I like having a tritium bead sight. Maybe a light mount and light for target identification. That's pretty much it.
I like the Meprolight for the tritium bead but there are a few others out there so you can comparison shop.
My preference for light mounts will always be for CDM Gear. Streamlight, Elzetta, Coast Products, Inforce, Surefire for lights. Do lots of comparison shopping here too.
If you haven't shot it yet, go shoot it before deciding you need to change the stock and forend. If you absolutely must change the furniture, I highly highly highly recommend Hogue.
You really don't need to spend tons of money to make it legit for home/personal, it already is. Again, shoot it first if you haven't already, spend money on ammunition before gadgets. Add the stuff that adds to the versatility of the gun, things that compliment and emphasize its usefulness. At some point, the things you add start taking away from the usefulness and hinder performance.
If you want to tactical it up, then go for. At the end of the day it's your dog and you're the only who's feeding it. You can turn it into a beast of a gun with a Mesa Tactical stock adapter and AR styled hydraulic buffer tube with a Magpul stock, full length rail and flip up back up sights and holo sight or red dot, receiver mounted shotshell holder, railed forend and vertical forward grip, single point sling... It's gonna look sweet but none of it is a surrogate for practice and none of it is necessary to make it a solid HD/SD firearm.
My opinion, the tritium sight and a light. That's it.