What are the spiritual aspects and the aspects of reality concerning this passage?
"No man hath seen God at any time and lived" is an example related to this passage, as well as the "live coal" being fire from the altar would have literally burnt Isaiah's lips beyond ability to verbally respond, saying, "Here am I LORD, Send me"
Did Isaiah get saved at this point in his life, or was he "commmisioned" to tell the "vision" he'd seen?
Why would a vision need to be literal in the way you describe?
The passage says that God is utterly holy and Isaiah is unworthy.
The purging of his mouth allows him to speak the prophetic word (examples of similar "mouth" events can be seen with other prophets--Jeremiah and Ezekiel especially, without the negative connotations of their sin interfering with the message).
How odd to think of an Old Testament prophet as "getting saved."
What would that mean for him?
The vision is told to present Isaiah as a prophet with the words of God in his mouth.
The words of the prophets are much more than what they see or hear in visions.