Both are great commanders with some overlap but have different strengths: Sauron is the best choice for a Graveyard deck
Worldwalker Helm Sorry Red fans, next is another Blue card, but you won't be sad with higher hitting stuff
It even has partner background to splash another color with some fun mechanics
For example, if you return two cards from your graveyard to your hand, discard one of them, then exile that card from your graveyard, you can activate Bonecache Overseer's ability that turn
Some partners like Jacob Frye and Evie Frye are exclusive and only have one other card they can be paired with in the command zone, so this pair counts as a Dimir commander
In addition, we run 2 Iono (Paldea Evolved) and 2 Professor's Research (Paldean Fates) to assist in drawing through our deck, with Iono also being a great card in many matchups where we will be playing down in the prize race