Lots'a questions.
It all depends on how much money you want to put into it.
Your ideas run the full spectrum!
The less you spend, the more chance you'll be able to recoup the value.
True CCHardening is the best option but $300 or so and you won't recoup that.
You ask a very good question about refinish for which much mis-information abounds.
It's been my experience that Ruger's re-finish/re-blue, based on those I've had done are the best that you can get and more reasonably priced than any local smith for a "new gun level" blue job. To me a factory re-blue that makes the gun look like it was a restoration to new is preferred. I believe a separate specialized team does the work. They are polished on the factory specialized equipment using the factory techniques. The flat surfaces are always flat, original factory contours are maintained/restored, and all lettering is clear and undistorted by over buffing. Note: as for any re-blue done by anyone, serious deep rust pits can not always be completely removed.
All the Ruger guns I've seen or had re-finished by Ruger look as good but usually better than any new Rugers.
Some want a custom blue, shinier than new and/or custom polished and are willing to pay more for that. That's fine. But most local refinishes cost more, are over buffed, and don't look as good as a new Ruger. Some look worse than the worn gun to begin with, and those will make you cry. (It's not unlike trying to get a decent car re-paint job.) And if you send the gun out, you'll pay shipping both ways, and wait who knows how long. The success of the final result is in the eye and the wallet of the beholder.
So it all depends on what you want.
Now consider these facts to make an informed decision:
Current Ruger cost for a revolver re-finish is $130 plus $30 return shipping from their website here: http://www.ruger.com/service/serviceFees.html And it will be returned in from 11 to 14 days.
You can request that the safety retrofit conversion be done for free including the shipping to Ruger; just call Ruger and they will supply a pre paid shipping label and usually a box to send the gun to them, and return ship it back to you for free. Therefore, no $30 return shipping charge as shown above if you request only a refinish.
Yes they will refinish the alum alloy grip frames and other alloy parts. It will not be dyed black and anodized as originally, it will be powder coated (a superior baked on finish in my opinion) like the current new Rugers.
Yes, they will convert your Ruger, whether you request it or not (no changes or machining are done to the revolver itself, only parts are replaced.)
Yes, your old parts are returned, with the exception of any specific part (not the entire gun) that is worn beyond a safe limit.
Yes, you can remove all interior parts and keep them before sending.
Yes, the gun will usually (with few exceptions) be stamped with an R on the bottom of the frame, under the trigger guard which must be removed to view the R.
Yes, the retrofit safety parts can easily be removed and the old parts replaced in the gun.
Yes, the safety retrofit will still index the chambers for loading; it is different than the New Model transfer bar parts. You still have to cock the hammer to half cock which is what indexes the chambers to the ejector rod and loading chute.
What do I do?
For old models, I always request the safety retrofit and ask for a refinish/re-blue as well. I remove and keep the original action parts and grips. I paid a total of $130 1n 7/14. I would also have new models done by Ruger and gladly pay the postage. Ruger service fees: http://www.ruger.com/service/serviceFees.html
Here's the last Ruger I had done at the factory. (I paid shipping for this Hawkeye because there is no Ruger factory safety retrofit kit for it.) I replaced the powder coated alum alloy grip frame with a steel GF polished bright:
Steel grip frame replacement:
Ruger won't do it but any NM grip frame made will fit on your OM. The only modification you'll need is an adaptor trigger to use the new model trigger return spring in the grip frame. If you consider doing this just ask for more details.