I just discovered Joe Konrath's blog, and he's got some great suggestions there. But what is your opinion on the paper weight? Do you prefer 24# also? I've copied my comment to him here: Joe, I used to submit all my stuff on 24# paper. But once Jenny Bent's assistant (at Trident) lost my submission and I had to get another to her fast. I handed it to her, saying something like, sorry, didn't have time to get thicker paper - and she told me, that's OK, this is better anyway. So I've been using 20# ever since - and I've got an ms. all printed and ready to go. Do you really think this issue is important enough to toss the printed ms?
I think you can obsess about a whole long list of things when you feel like you're beating your head against the wall to get someone to read your work. Paper weight is just one of them.
As long as it's white (and I can hear someone somewhere whispering 'ivory' 'ecru' and 'bone") and the ink is black AND the font is crisp, you're good to go.
Yes I notice brighter paper. Does it make any difference at all in my judgment about writing? No. Do I remember "oh you're the one with nice paper" when I sign you up for the big dance? Newp.
Worry about the passive voice, innovative description and character development. Don't worry about the paper.