It's not a full game obviously but pretty much all the basic elements are there. Building construction, unit building, melee unit, range unit, builder unit, attackable building, unit command, etc.. Forgot resource gathering maybe. When I decide to take a break from my MechCorp again I guess.
So back to the point, Unity navmesh is pretty awesome. It would be perfect if the navmesh can be dynamically updated/edit in runtime but that seems to be a pro feature in 4.3. But you can still get quite a lot out of it. A RTS even. but you will need to compromise a bit. For RTS, that means buildings can't be placed too close to each other. There needs to be a gap large enough for the agent to move through or they will simply got stuck between building. Then you can only use NavMeshObstacle on the building to block any walkable area. Which restrict the building footprint to a circular area, which occupies much more space than it needs to avoid unit clip into building. Put this two together, it means that the building must be placed quite far apart. much more than what it seems to be visually optimum. Even then the unit navigation may still get a bit wonky when trying to move through an area with concentrated building placement.
All this bring me to another delicate matter, PathFinder. I'm afraid the simple fact is it has became obsolete. Unity navmesh is simply a better solution. I'm considering to take if off AssetStore. Hope that doesn't cause any issue or upset anyone.