I don't want: to serve advertisements, to force people to link to their identity, to cause friction to an already engaged user (no signups form / no captcha), to feel like a bolted on service / widget (I want to feel like part of the site), cluttered ui with to many options.

Hard to put into words the things I don't want Remarkbox to be.

Disqus started with a similar goal, but they had to make changes to make money. What will give you a different path?

Charge site owners for the value added. Stay small but still turn a profit. No investor money so not forced to grow and sell out user base (no ads).

Only add useful features to keep user experience decent.