Kaalia is a commander, almost never an inclusion in the 99, and being Modern-legal has meant nothing, she hasnt been featured in any Modern decks of relevance
There were concerns when it was first previewed that The Soul Stone would end up as an auto-include in a ton of Commander decks
In previous years our members of our gaming group have bought some decks for toolboxing
Seeking divine aid, they built a small shrine as an offering and attracted a Kami of Shared Purpose
This can be used in politics regarding other players, its a gate that can be fetched with other cards, and it works wonders with mechanics like dethrone
For example, if youre building a deck around Urza, Lord High Artificer, you probably want a ton of cheap artifact creatures you can tap for mana, and then big heavy hitters you can cast with his second ability and all of that mana you generate