What do you mean by big-box competitors? Can you give me one name so I can see how you define "big box?" I'm assuming you have a more innovative approach than your big-company competitors, so you could theoretically charge more. Particularly if it's b-to-b.

Also, personally, I'd try to secure some medium to large company clients as soon as possible. Small businesses, while wonderful (your offering is one, after all), often don't have the size budgets you'll need, nor the influence, to take you to the next level. However, try to avoid or de-prioritize the "whales" (e.g., Fortune 500) in the first year, as they'll often consume a lot of your time/resources "kicking tires."