Summons of Saruman is amazing since it essentially works with all themes of the deck: amass orcs, fill your own graveyard, then cast another instant or sorcery for free
If an opponent is instructed to put a card into their graveyard without using the word "mill," The Water Crystal's second ability doesn't apply
Most often, they are low-power, high-toughness creatures, which means that without some extra support, they are usually good at blocking (and making mana, for some reason) but aren't very good at actually killing the opponent
You have a lot of wiggle room when making a Jodah deck, as the only qualifier is that it contains mostly legendary cards
I say go with your favorite one
Gisela, Blade of Goldnight is a seven mana Red/White 5/5 with flying and first strike