Domain parking questions

I've had a good search around and I am most of the way there but I just had a couple of additional questions to make sure I have everything right.

Here's where I am up to:

1. Domains registered
2. Forwarded to Sedo Parking pages
3. Parking pages somewhat optomised
4. Done keyword research and getting about 40k global searches with little competition across 6/7 search term varients.

I want to submit to search engines and bump up the rankings on target search terms. However, as it is just a parking page am I risking anything or am I fine to have no content? Also I am having trouble submitting more than one search term for the Sedo parking page - further some of the Sedo adverts are good and others are totally irrelivant, can I promote the better ones and get rid of the dross?

So next I am thinking:

1. Submit to search engines
2. Build a few back links but nothing too much
3. Add more keywords if possible
4. Hopefully cover registration costs until the event when the domains will be worth somthing.

Sorry, some of these questions are probably very noobish, my knowledge is quite patchy at the moment.