I would make sure it can host IPSC, SASS, or IDPA matches. That is a great way to develop a core group of "regulars". I've done matches at indoor ranges. The key is to be able to open up the indoor lanes so it can replicate an outdoor open bay as much as possible. We would take breaks while they changed the stages if there were not enough bays (I think about 6 bays is the minimum needed to not have to do this).
A covered picnic area with some tables and maybe a BBQ pit would help keep those folks around after a match.
Being able to host visiting instructors would also bring in lots of new people and keep your regulars happy.
Plumbing and CLEAN bathrooms are key for the women folk. Sounds like you will have electricity and running water, so making sure there are good facilities close to the shooting will go a long way towards getting women out there. Men survive with a leafy bush