If you say your message is bland and uninteresting, why send it?
If you have a decent list, you're only going to burn it out by sending garbage.

Here's a basic mailing question list:

Does the IP you're mailing from have rDNS ?
Does your rDNS have a valid forward dns ?
IE: 1.2.3.4 = mail.yourmachine.com
mail.yourmachine.com = 1.2.3.4

What is the source of your list? How old is it?

Are there 'sex' words in the message? A lot of sex related words will cause messages to score high with spam filters.

Are you sending a mostly HTML message?
Are you linking to a domain in the message or an IP?
Are you sending a really common spammy message ?
...