In these situations, combat tricks and fogs are great
For example, The Haunt of Hightower benefits from cards entering your opponents graveyards, so youll want to focus on cards that destroy your opponents permanents, like Finale of Eternity, and cards that make them discard, like Awaken the Erstwhile
Some of the best ways to get this kind of value are cards with enters abilities
Wizards announced that these cards will also be available in Wizards Play Network promo packs during the Core Set 2020 play season, appearing in roughly a quarter of packs
I wouldnt want to play this deck in a world full of green creatures like my last list above, but if thats where things end up, you could always play some Lifebane Zombies
My experience so far is that shes fine getting into the red zone with buffs from Arahbo, but in case you want to play more defensively, you can add a way to tap her without attacking, like Selesnya Evangel or the ever-popular Springleaf Drum