Actually, I had a hard time, for many years, incorporating into my practice many figures such as Kannon and Jizo ...
I have some cautions I would offer both to people who say (a) these things do exist in a concrete way, and those folks who say (b) they do not. While both those extremes may be correct (only the universe knows for sure, and I remain an open minded mystic-skeptic), I have come to see "them"
as archtypes, representing real characteristics of human life and (since we are just the universe) thus the universe.
In other words, in a nutshell: When we feel in our hearts and act upon love and compassion, thereby love and compassion exists as a real, concrete aspect of the world which our hearts and acts create. And since, in our view, there is no "inside" or "outside" ultimately, what is inside you is just as much "the universe" and concrete reality as the moon, gravity and the stars. That is "Kannon", in that way a real and concrete aspect and 'force' of the world.
I believe in Buddhist Heavens and Hells, Buddhas (apart from the historical Shakyamuni) and Boddhisattvas, and all the rest of the Buddhist cosmology, in much the spirit of that famous essay ... "Yes, Virginia, there is a Santa Claus
". Did you ever read that? A little girl wrote to a newspaper editor, back in 1897, saying that she'd heard from friends that there is no Santa Claus. "Is it true?", she asked. Part of the response ran like this ...
What? You don't believe in Santa Claus?
GassHo Ho Ho, Jundo
VIRGINIA, your little friends are wrong. They have been affected by the skepticism of a skeptical age. They do not believe except [what] they see. They think that nothing can be which is not comprehensible by their little minds. All minds, Virginia, whether they be men's or children's, are little. In this great universe of ours man is a mere insect, an ant, in his intellect, as compared with the boundless world about him, as measured by the intelligence capable of grasping the whole of truth and knowledge.
Yes, VIRGINIA, there is a Santa Claus. He exists as certainly as love and generosity and devotion exist, and you know that they abound and give to your life its highest beauty and joy. Alas! how dreary would be the world if there were no Santa Claus. It would be as dreary as if there were no VIRGINIAS. There would be no childlike faith then, no poetry, no romance to make tolerable this existence. We should have no enjoyment, except in sense and sight. The eternal light with which childhood fills the world would be extinguished.