Selling yourself

No. Everything I've read about queries is to not use that. It's like a "so what" tidbit. The only thing that might be useful are the comments from professionals, like teachers, but I'd recommend sticking with your story.

No. Never. Agents HATE when you tell them your kids or neighbors or whoever loved your manuscript. That means nothing to them, and think about it, why should they care? You wouldn't walk into hollywood and say "I have a great script. My neighbors loved it and they watch movies!"

It WILL hurt your chances most likely.

I'd also like to echo what others have said so far. Don't try to sell your work by telling the agents or editors you've submitted it to, which people liked it. Instead, sell your work by telling them about your work.

I know what it's like to think that my work is garbage because I'm a newbie writer, and that somehow I have to prove my work is good by telling people so-and-so person I know liked it. I've learned that, like Miss Snark used to say, "Good writing trumps all." So focus on your writing and your story when talking to agents or editors. Let your writing and storytelling quality speak for itself.

And best wishes to you.