What about:
1) You can't be allowed to start a topic before your second post. Any attempts will guide you to the preview page, and the "Introduce yourself to CF"-topic will be linked to. This will solve the problem adressed in the third option.
OR
2) New member starts new topic -> presses "Submit" -> Is taken to "preview", where he's given a message along the lines of "Welcome to CF blablabla... this is your first post, and to keep the forum tidy, we kindly request you to look over your post to see if everything stated is relevant and on-topic, and properly spelled. This will usually give you a warmer welcome, and more serious replies. Please do also check the forum to see if the same thing has been posted before" Or something. Britons are way better at polite messages than me.
3) Limit on how many topic you can start in the same day. Can be lifted for special occassions, and does not affect mods.
4) Ban any topics with the word "Thorpe" in the title.
Give me more time, and I'll will give more ideas. It's late now, and I slept little tonight...