Kuhnhausen states endshake should be corrected once it starts to reach beyond .006". He recommends correcting to .001".
If you're going to fire magnum loads, I think endshake should be corrected sooner because of the greater stresses from the magnum rounds; endshake only increases with use, especially with the boomers.
I'd say you did right correcting at .004".
You want that .001" endshake dialed in as part of the correction to account for any slight tolerance variations and avoid stacking tolerances that might bind the revolver; also, to account for thermal expansion under fire to, again, avoid binding.
You're fine with .002".
If this is a defense gun, run it at the range and confirm proper function before returning it to the defense line up. Any change to your firearm requires this check. At minimum, check your headspace and dry fire empties or snap caps.
I once corrected endshake in a functioning revolver I'd fired hundreds of times. After proper endshake correction and confirmation of adequate headspace, I took it to the range and it bound up under fire. Turned out there were miniscule burrs on the blast plate that the cylinder was clearing only because of the excessive endshake, but bound the action once the endshake was corrected, and had to be filed down.
If I'd needed that piece and hadn't checked first after making a small change that passed ordinary inspections, it would have been bad.
Make a change, hit the range.