Hi Stephen,
If I were you I would run the page through SEOmoz On Page Optimization Tool, I used this and transformed my page from an F to an A in about 20 mins. That said and judging by what you are saying, It doesnt appear to be key to your campaign that the homepage is the most visible from an SEO poiint of view.
However running through ther optimzation Tool you will find that you dont need to be stuffing your page with thousands of keyword's in order for it to look appealing to search engines, a couple of key phrases subtley faded into the design of the document will suffice, if your using images be sure to use any desired keyword in the Alt atributes, you also have as you said, your title, H1 and there is your Meta Descrip. Possibly use bold for your H1 but reduce the opacity considerably so as help merge with your page design and not be obtrusive but also gives your page some SEO Kudos so to speak.
Dont use the Meta Keywords Tag, possibly also add the prime keyword in your URL for that page but try and keep it short and relevent and the same as your H1, if it is more than one word then separate it with hyphens.
There is quite a lot you can achieve with minimal content on this page as long as you ensure that everything else you do is done correctly, I am redesigning our site at the moment and a minimal homepage is my kinda trip also.
Anyway hope this helps but do have a look at the Tool, it will provide excellent guidance, not just for this page but all pages within your site.
Kind Regards,
Craig