You mean you used sonarr to rename things incorrectly. Sonarr didn’t do anything other than exactly what you told it to.

I think you may be the one lacking intelligence here.

Just run things and find out. It really depends on your network and environment. Take note when things act up or slow down and scale back.

I usually have over 1,100 torrents seeding but maybe a dozen or so are active at a time. Maybe more sometimes, I don’t watch it as closely as I used to.

A few times I’ve added hundreds of movies at once by importing IMDb lists and experienced network errors. I had to download them in batches.