Unreal engine means mod support will probably be next to nonexistent unless the devs go seriously out of their way to make it happen. So I don't expect much replay value out of this. It will probably disappoint the way MW4 and its sequels did.
Frankly a fan-group could do better than PGI, and if they did they could take their effort directly to Microsoft and say "look, we have a vastly superior product that can make you a lot more money than PGI's incompetent scribblings, just give us the OK to use the IP for a single player game". And in a rational world, MS would jump at the chance.
And I say this having recently started playing MWO again and noting considerable improvements made in the last few years. It's still amateur hour at Piranha Games.