Didn't really get what you are doing while browsing the start page. Digging deeper helped though.
Not sure if you need a video, I think more people don't have the time to watch a video anyway.
That's the problem with landing pages. They're always hard to design objectively when you've worked on the product for so long. I'll think of some optional wording for headings etc to better explain it.
Instead of the 3 points after the fold I would rather put up 3 easy steps.
eg:
1. create your mailing/printout/letter
2. merge the data
3. print and send
pretty much like the "3 easy steps" you mention in the tour.
The current 3 points on the landing page sound rather empty to me.