Serving your site through a Tor hidden service will indeed prevent the general public to learn your identity through technological means.
But as you said that you would operate legally, I would worry as much, if not more, about the threat posed by conventional private investigators. Because they won't even care about how is served your site, they will hunt for your company name which should be fairly easy to find, then will go in length to find the actual owner.
The book How to be invisible by JJ Luna discuss thoroughly issues more or less related to what you want. I would suggest finding it in the electronic format, so as not to risk to attract unwanted attention.
This is actually the major leverage that you can use to protect your identity : don't let anyone have a reason to find out who is that site's operator.
And it works also the other way around, if this is also of your concern that somebody investigates you personally to end up discovering your business.
A good way to protect you is to create an alias name, a true spy-like covert identity that would be the closest to impossible to link to you.
JJ Luna talks about some techniques to achieve this.
But to answer your actual question on Tor, yes it gives you a really good asset although it is not immune to fails : especially in that any mistake on the server management risk to expose its real IP. You should consider using a gateway (same as a transparent proxy but for serving content instead of being the client) to Torify the traffic.
- Tor is a huge step towards your goal.
- Tor can fail.
- Other ways of unmasking are equally important.