You want Karametras Blessing over Kayas Ghostform because losing all the other Auras on a creature is a significant setback, and sometimes +2/+2 is just lethal
That's a deck about getting just a bunch of characters out and just Questing [gaining points] really fast Emerald & Ruby is really, I think, the most strategically complex of the three
Yes, in terms of depth and card interactions, other games dont go as deep
Likewise, if youre playing Gishath, Suns Avatar or Zacama, Primal Calamity, then 37 could be just right or perhaps you need more ramp spells to get your Commander out quicker
It could see play in formats where generating a lot of tokens is beneficial, but its effectiveness may be limited compared to more powerful options in competitive settings