Beta readers
This is my view.
1. I looked at critique circle, and found the critiques not to my liking. It appeared most giving feedback had little solid critique experience or training. I am experienced at critique, reviewing manuscripts, judging contests, beta reading--you name it. Just because someone is a writer, doesn't mean they know how to analzye writing, and vice-versa.
1a. IMHO, even online critiquers who have experience in the writing/publishing field, aren't often good beta/critiquers. Knowing how to give constructive feedback is a separate skill.
2. My opinion, having looked at online critiques, is that newish writers use them. Hence more of 1 and 2. I advise caution.
3. I think you answered your own questions, Elonna. Depending on the piece, the audience, and your goal, use your best judgment about who you show it to.
4. There is a school of thought that critique is actually collaboration. Do you want that? No worries.
5. Another school, (and there's a great quote by Hemingway about this but I can't recall it) is that by telling my story to others, by allowing them to read it before it's done, takes away the energy to tell the story further--to complete writing it. Once I share it, the work is done. Another mainstream author says the same thing; I can't recall if it's Annie Dillard or?
6. You'll learn from trial and error what works for you. I shared a piece, written as an example of horrible metaphor, run-on sentences, and extreme adjective to the workshop I facilitate. As I read, intending to tell them at the end, "this is what not to do" they were laughing and laughing. They said, "we didn't know about this side of you, give us more!"
7. I know some writers use beta readers all the way through; many use spouses (and claim nobody ever, ever critiques their work until it's done/sent for publication--sure.)
8. When people hear you're writing, they ask "let me read something." Trust your gut. I may show them articles I've published, as a test. If I trust them, I may show them a novel excerpt at some stage. I've found friends mean well, but it's partly that, as they tell me, they want to say "I knew you when" and "so if I read this will I be in the dedication/acknowledgments?"
9. An effective method for beta-ing yourself is to read it aloud to yourself. Or, have someone read it to you. (Have a double espresso near-by as a reward.)
10. Good luck!