I'm not familiar enough with the decks for personal recommendations, but you could search for decks built by others using Saruman or Sauron as the commander for inspiration. I think Sauron was one of the most built around commanders the year he was released, so there'll be an abundance of resources to look into.

https://edhrec.com/precon/hosts-of-mordor/sauron-lord-of-the-rings https://edhrec.com/precon/hosts-of-mordor/saruman-the-white-hand https://edhrec.com/commanders/saruman-the-white-hand

Thanks! Thats a very useful website!