Congratulations on getting a nice rifle!
I'm also looking at tuning up a new 112 BVSS but mine is a 7mmMAG. If I could afford it I'd buy another one in .300WM but I only get one rifle a year.
I don't see much point to machining on the Savage bolt face or lugs, or sleeving it either. The floating bolt head avoids the bolt face rocking issues that happen in other actions unless they are sleeved.
With regard to bolt stiffness: Get some Lucas #2 Red and Sticky lube at Tractor Supply or an automotive parts store (it comes in a grease gun tube full for less than 3 bux) and a Monoject 412 syringe
and you will have a life time supply (and then some) of good bolt lug lube. Apply it sparingly to the cocking surfaces, between the floating lug and the recoil lug, and the ejection ramp on the back of the bolt. The bolt will break in after a while and be quite smooth. I racked mine a hundred times holding the trigger to make it cock each time and it is noticably smoother already.
It It also isn't necessary to pin the recoil lug on a Savage if one uses the right recoil lug - one designed to be used with a Savage that has the indexing lug on it. Precision ground recoil lugs specifically designed for Savages are available from Sharp Shooter Supply.
It does make some sense to true the receiver front face and I've done that to all my Savage actions and a couple for friends but can't assign any particular accuracy improvement to it. I've machined stubs to hold barrel nuts to true those because they take the place of the shoulder on a normal barrel tenon, but again can't assign any particular accuracy improvement to that either.
My 112BVSS (7mmMAG), brand new, needs to be recrowned because it has a tiny burr on the crown but the bore looks really good (did a borescope examination today) after 5 rounds of brake-in cleaning between each round. It will get another 5 rounds of single shot breakin-clean before Friday when it goes to the range the first time.
Trigger breaks at a nice crisp 2 lbs out of the box. I'll leave the trigger alone although it is a pound lighter than I think is optimum in a hunting rifle.
About the only thing it may need other than having the crown touched up is a good glass pillar bedding job. A good bedding job isn't hard to do. I replace the factory pillars when I do it.
One of the nice things about these rifles is that not much is needed to make them into really good long range rifles since they basically start out as good rifles right out of the box. If all rifles were as well made as these 112 BVSS rifles gun smiths would go broke because they just plain don't need much customizing and they are heavy enough (mine is 13.0 lbs with scope mounted) to not need a muzzle break.
What's to not like?