I'm getting practice taking criticism with the test readers. I got used to it from my English teachers in middle school, too. You just develop a thicker skin. 
Totally saying it sucks won't fly with me, but if you give me a good reason why Susie Q can't be living on Venus without a special space suit, I promise to rethink my logic and investigate, go back, and edit!
I prefer character driven stories.
I've only been able to write first person in short story format. In novel format, it's too darned limiting for my taste. The omnipotent, all-seeing narrator POV works best for me. It's the most common POV in SF and Fantasy novels. First person works for certain things, but I prefer exploring the psyches of my other characters, rather than just ONE in first person.
Plots are rejectable... I've ditched entire chapters because I haven't been able to get something to mesh right. I'll start over! Writing really doesn't have set rules--pros will tell you do what works best for you.
If you make your deadline and the book is published, the editor is happy.
I have to get some stuff finished first to market--I've researched HOW, now is WHEN... That annoying day job means I write after work, on weekends, on paper if I have to (I need a laptop!), and type it up later.
Harlan Ellison, a well-known SF writer (he won't say he's SF author, though, he's a little strange) can sit down and WRITE start to finish, a short story with a type writer from an idea someone handed him on a piece of paper. He did that as a challenge once. He's Mr. Opinionated, and he consulted with the creator of Babylon 5 TV series on how to make his story for the show better.
I read one of his short stories in Asimov's SF a number of years ago about a computer turning into a vampire--now that was funny and very creative... (The keyboard bit his character!) 
I'm a little slower at getting finished, though.
Pace yourself and do what works for you. Not everyone has a full 8 hours a day to write. I don't, and I've met pros who still work in other fields. Writing is extra income for them.
My uncle is a retired school teacher.
John Grisham was a lawyer, Michael Crighton worked in the medical field (Jurassic Park).
Mercedes Lackey spreads herself out more by co-authoring a lot of books with newer SF/F writers. More books=more sales. She also has no kids to speak of and didn't do this for her living in the beginning. So anything is possible! (She rehabs injured birds of prey and has a license to do that, so when she describes these birds, she has first hand experience handling the wild creatures.)
Yay!! Go writing team!
JM
