I hate to be 'that guy' but have you looked into what's involved in the making of any game, let alone something as complex as an RPG? Because damn. Code. Srsly.
Unless you have someone who has made a number of games in the past on your team, don't try anything that needs much of the following things:
- Physics
- Pathfinding
- Precise hit detection
- Regular view/location changes
Those things in particular are technical nightmares. Action RPGs need teams of experienced people working on those things to get them good. Stuff that relies on simple number crunching is the best bet so: points based, turn based systems is the less scary route to take.