This card looks, on the surface, like a tweaked Blue Suns Zenith
White Rhystic Study Although mono-white card draw has been getting better recently, White Rhystic Study would still be a great inclusion alongside a mono-white Commander
Switch out one card at a time, consider how you could have avoided the outcome and keep that at the front of your mind in the next game
Blue has good ways to mill yourself or just draw and discard cards
Black-green is one of my favorite color combos to begin with, and Eldraine is full of fun cards like Bake into a Pie, a black instant that destroys a target creature and bakes them into a Food token, Sweeney Todd-style
Dimir mills itself pretty well, giving Raul a steady stream of cards to cast, plus some synergies with Secrets of the Dead and Prized Amalgam