Hey my 2 cents is you've got a fine rugged work horse, the ruger P series is not sexy in any way except that if you leave it alone it will eat about any ammo, run dirty or clean, It is not a tweakers gun so there isn't' much in the way of after market stuff.
Spend your upgrade money on ammo and training,
but besides some good black on black sights I would leave it alone.
I have the rubber grips on mine as well. Other than those buy ammo.
they aren't a great carry pistol weight wise but they are dependable as heck. Holsters can still be found too. I USED to carry mine before lighter pistols came around.If you plan on carrying it, one of the best aftermarket upgrades I've seen is a good back brace. Just kidding, it's a great pistol