Good points. Knowing when you are truly ready is the hardest part, none of us submits work that we think is crap, and feel offended to find out that it is.
I've recently discovered Critique Circle, which not only helps with getting your work critiqued, you have to critique others' work which is a great learning technique. "Peer-to-peer" on JW is great, especially being more UK-oriented, but it doesn't have the numbers of participants or the immediacy of responses. I hope Harry & Co. don't mind me mentioning it.
Re. edits, I've always struggled to count how many edits my work undergoes, I think we're all different and some people are more analogue than digital. For me, I've now found a year after starting to think seriously about submission, a year's worth of intermittent editing a work is barely sufficient. And, external criticism is more important than how many edits you do.
For any debut author, I cannot recommend highly enough the medium of short stories. For a start, it's easier to find people to read a sub-10k word piece than a 70k+ novel. You can do so much more, and get it reality checked in short story competitions, without the depressing process of successive rejections or silent dismissals that you inevitably get from your first novel. You still won't get published, unless you are the one in a thousand genius that doesn't have to worry anyway, but the pain is far less and it teaches you the craft.