[ax0n]

A cautionary tale: I had good luck with ZoneEdit when they launched. It was/is kind of in the same space as this. Their new UI is okay, but yours looks a bit better. They started out with freemium, but eventually had to re-structure how their premium service worked, and in the process crippled how the free service worked. It got bad enough that I abandoned them.

Be very careful how you structure your premium offerings. People don't like when the free version starts losing features or capacity.