There's no such thing as an unbiased yet useful search engine. The very act of choosing which article to put at the top is a value judgment, therefore a bias. The only way to make things "unbiased" would be to rank the matches randomly, and that would be useless.
So would the SEO people. But even disregarding that problem, to have a halfway decent search ranking you're going to need deep learning, and you'll get a model that is largely opaque.
When I said I wanted control over the ranking, I meant as a user. Tell me what parameters I can rank on; give me a UI that makes it reasonably easy to express a ranking. That's it.
I hope UI design and stuff is orthogonal to the construction of an open index. I think this could be very interesting.