First off, I think your product looks and sounds great! Whenever somebody posts a request like yours on HN, I always go to the link right away, so as not to be influenced by your HN description. Then I read your description, and it is amazing how often the description on HN is different from what the website says. Yours is a perfect example of this. Your whole description of a "Knowledge Management tool and Collabora…
I'll support the contrary viewpoint that you should limit your audience. You can't have a new product targeting both professionals and consumers. These are very widely different markets, that buy differently, that you'll reach differently, for which you need different messaging, features etc. For a new product, the more targeted and focused your audience, the better. "for professionals" for example is far from target…
"for professionals" is both not specific enough and also far too buzz-wordy. A good market for this might be help desks, or small startups that offer round-the-clock support. Round-the-clock support usually means at least one person per shift, and small startups don't generally have a lot of overlap there -- so they have an increased need for quickly findable knowledge, which means that they need knowledge management.
Target that, or something like it. If you can niche further, do it -- if that niche gets traction, expand it slightly. If it doesn't, change it altogether. Expansion can occur in the form of a new site with different branding or subsites.
There are plenty of startups that make accounting software, but of the ones I've worked with, the one killing it the most is the one that makes accounting software "for landscaping companies". If you're a landscaping company, looking at a hundred different accounting packages, your choices are now limited to the best known (e.g., Quickbooks), and/or the ones most specifically targeted to you. You won't win that comparison every time, but you'd rather be in the top 3 90% of the time than in the top 100 100% of the time.