The Upload Spreadsheet button without any auth or form required is great. For any prospective users looking for this feature your time to being useful to them is approaching the theoretical limit. Only way faster would be to embed a small version of that page's form somewhere on your main landing page...

I really can't think of any other suggestions - your landing page is excellent, fast and I imagine highly converting with all the social proof. I also like the specific landing pages for each customer segment a lot, I really need to do that for my service.

Your site inspires me to work more on mine!