The most promising side in my opinion is probably the workshop integrated mission maker and pilot log side of things. Having 'ARMA 3' level mission/unit workshop support would be great. Some gameplay would be great in a high fidelity GA flight sim world, plus an easy to use MP set-up.
Dovetail's M.O. is usually to offer the base platform pretty cheap and then DLC it to death (not in a bad way, just that they offer their $40 price points 'per unit/train/aircraft/airport' etc).
The graphics I have seen so far look fairly plain (early access!) and pretty close to what we have in FSX/P3D, and something I'd be disappointed to get if I used Ortho2XP properly (the price gap between things like semi-legal Ortho2XP, Orbx and custom maps in terms of quality/price is crazy), but the true value will be in how well that new engine pumps out frames per second on multi-core, multi-X systems. A high performance FSX successor with a 2nd go around at a 3rd party ecosystem might be good.