Hey there!

Hmm, nicest actor is difficult for me. The /entire/ cast of Lost in Space plus Anna Sawai.

On Lost in Space the whole main ensemble (and supporting cast) were just so thrilled to be there, it was like being with a real family. I only joined the series for the final Season but the love they showered everyone with was unbelievable.
Taylor, Mina, Parker, Max, Ignacio, Toby, Molly, Ajay, and Brian (Robot) made every day a pleasure to be on the show. They took the time to be kind to every one of us from the production assistants to the security to the carpenters.

Anna Sawai I have worked with now on three shows, Pachinko, Shogun, and our currently unreleased Apple+ series. She is always kind and pleasant, and very talented. I'm biased though because she always compliments my Japanese when I practice (Shogun took 10 months and most of our cast/background were Japanese, and the people training them didn't speak English. Figured I'd learn to bridge gaps).

My least pleasant experience in film was dealing with Ezra Miller on The Stand. For obvious reasons I won't get into details here - but needless to say that the behavior you see in the news is par for the course and none of the crew that I've spoken to since has been surprised by the revelations. Sadly, Hollywood loves to protect idiots it seems.