While Daxos is a fantastic commander with plenty of unique strengths worth building around, Siona has different strengths that set her apart from Daxos
Play a forest, get a 5/3
Savvy players will try and bait out counter magic from you before playing the spells they really want to resolve, so you must learn to ration your answers but at the same time not allow game-winning cards to resolve if you can't deal with them later
Theres often a bleed with artifact strategies, but sac decks, whether low to the ground Mayhem Devil things or bigger ideas like Korvold, Fae-Cursed King, like to have fodder
Snapping Voidcraw Mana dorks that generate two mana per activation always have a place, and Snapping Voidcraw also can also draw you cards in a pinch
These included cards like Arcane Sanctum (taps for white, blue, or black) and Crumbling Necropolis (taps for blue, black, or red)