It depends on what the focus of pfsense is? and what the developers define as a successful project.
Distrowatch has hundreds of distros and projects each with a focus that is successful or not so. If a definition of success is the sheer number of users and the size of the community, then features are critical in the development of a distro. There are a number of projects in the firewall space each with their own advantages, however if pfsense is to become a hugely successful community then looking at firewall project features that are popular is important as this will attract interest to develop a community.
For example IPCop is sucessful in that it has had 2.5 million downloads for the 1.4 series, however I do not think the project developers are aware just how much the addons with features such as content filtering and client side friendly VPN projects such as OpenVPN popularize the project.
Given this, how does a development team decide what will be a successful feature?