While it is slow, Mysterious Candy can be helpful if resources are scarce in a run.
Because of Number One's synergy with Brimstone, it is highly recommended, despite the Health cost.Butt Bombs gives 5 extra Bombs to start with, which can make items or Secret Rooms easier to find in the first 2 levels.Dirty Mind spawns friendly Dips when a poop is broken, making E.Skatole is a highly useful item, due to the amount of Black Flies it creates that can be transformed into poop.Enemies that do not do contact damage ( Fly, Mulligan, Host, etc) are valuable, as they can be transformed into poop with no drawbacks. Given the short range granted by Number One, enemies will be more likely to do contact damage. Turning all the enemies into poop allows for rapid clearing of rooms, and Petrified Poop increases the chance of those poops containing pickups.
The starting item set grants Isaac the Oh Crap transformation, significantly increasing his survivability. Getting close to enemies is required to defeat them. Starting with Number One limits Isaac's range significantly.
