Backend as a Service

I am new to the forums and was wondering if any you would be kind enough to help me with my project idea.

The plan is to build a Backend As A Service for developers to freely deploy on your own rented or hosted server as well as mobile framework. I know a few companies have this done already such as BassBox, FireBass etc, but my I want to improve upon these services and provide a free service instead of paying some of the crazy prices.

What do you guys think? What pros and cons do you see with other Mobile Backend as Service?