It can be whatever the person or situation needs
When I send healing, I work very closely with God and the Arch Angels. The Arch Angels, least Michael I know is listed and talked about in the bible. Many times yes, I do use my guides and angels (this includes the Arch Angels also), but I state that only workers of the light being present. When I say this, I mean only of God's light. I don't use any other because of my beliefs. I also don't honor any other god, but God himself.
When I had my first attunement for Usui Reiki, I saw God. His flowing robes, the gold of the walls and light torches, even his hair and beard. When I was presented to Him, He opened up his arms and said "Welcome Home". I cried when my attunement was done because I had always wanted to "see" Him without having to die to do so. Before my attunement, I asked God to help me with it and bless me with the attunement if this was the path He wanted me to take in my life. That is when I was blessed to see Him. So far I have seen Him twice now in my lifetime.
Guides and angels are works of God. Which is why I use them. It is totally different from having a passed loved one come in to heal a person, all though I have done that on a few occasions because their loved one wanted to help, and the client wanted their help.
I guess basically what I am trying to say is that it depends on what the person or situation needs. And what the other person is sending. Because I believe in God, and I work with Him, I know that I wouldn't want Buddah or someone else to be there that I wouldn't think appropiate for my healings or anyone else's, unless that is what they believe in and asked for it.
HH