I don't think there is much real life dope on that subject but lots of opinions and theory, which is fine as long as each is properly represented. I have no long hour data but I have owned a few CS types that were "show" engines and thus I had them slowed down quite a bit. After reading about lubrication problems (that I had not thought about) I removed the crankcase door from one of them that had sat a long time just to verify what it looked like inside and then replaced the door. I started the engine, ran it for a minute then shut it down. As I remember this was around your RPM spec. When I removed the door I was totally satisfied that nothing was starving for oil for my use which was powering nothing. You can preform that simple test yourself.
Variables here are of course the loading. Another one is the type of internals you are dealing with. Remember I was dealing with a real CS, thus an oil pump and a dipper, bushing mains, and a shelf type sump. You get a lot of oil thrown from the crankshaft when your pumping oil to the mains that you don't have on a pumpless engine. On a 'roid you could turn the dipper sideways for more splash or even make up a custom one that would drown things in oil even at 100 RPM if you so wished.
Governor control at low RPMs is going to get funky no matter what you do because the camshaft is only going to be turning 175RPM at your spec. Control will always be improved by using the lightest and longest spring that will give the required RPM. In your case the weights might need to be lightened also. I wouldn't do that as a first step ,but the last one after many springs were tried.
Butch