Well I have used BRASS pins for 10 plus years on nickel plated as well as brass 300 WSM cases. Used Lemishine, Dawn and covered the cases with about ½" of water. Now I use Cream of Tarter instead of Lemishine when I can find it. I've used Federal Nickel plated, Winchester Nickel plated and brass, Norma brass, Nosler Brass and one other I can't seem to recall. After 10 plus reloads on the Nickel plated brass I can now see where the nickel is wearing off, or should I say fading off. I use to clean and tumble my cases after every firing. Found that it did not improve or hurt accuracy, precision, case life, or anything else. No advantages or changes to ES, SD or velocity. I even left it running for 24 hours by mistake one day. No peening no nothing except shinny cases. Last I checked my shinny cases really never helped my reloads. Might look nice, but no benefit. IMHO. Have not tumbled any case for the 300 WSM in over 5 reloads.
Now for my .45 ACP that I use a Dillon 650 for, I have been tumbling the 45 cases. I sometimes get range brass from others commingled and I think, but not sure as of yet, it might seem to help the Dillon run better. I'm even beginning to question that from the smoothness of operation.
I do anneal my 300 WSM and all other rifle cases after every firing, which extends case life. It also has improved my consistency with velocity, accuracy and precision. I use maximum loads and I have close to 1,500 or more rounds down my Savage 12 BVSS and it's original factory barrel. I clean the primer pockets, but not to the point of see myself reflection, just get the residue out.
To me, IMHO, all the brew ha ha about tumbling and excessive cleaning of cases is a waste of time for what I do. The benefits are not there for me. I guess after almost 50 years of reloading I must not be learning a dang thing. Oh well, back to learning to read the wind.