In that situation, not only is Summer Bloom free, but it generates mana, which is easy to convert into a Hive Mind or a Primeval Titan to end the game
With how many ways there are to tutor cheap artifacts and Equipment these days, that shouldnt be a major problem, but its worth bearing in mind before you add it to your Commander deck
Even though Dihada is geared towards Legends, you can run plenty of non-legendary Angels alongside your legends
A 2/1 and a 1/1 flier is already a great deal for 2 mana, but those tokens are artifacts, which opens up many more synergistic paths, and you often get more than just that first thopter from Loyal Apprentice
First, there needs to be something worth copying when it enters the battlefield
So while Enlightened Tutor, Vampiric Tutor, Worldly Tutor and Mystical Tutor are right out, Personal Tutor is probably fair enough