It will beat Sim city 4 with Mods for sure.
That would only happen if the game core mechanism offers enough potential for it.
There's been various examples where the community didn't catch, sometimes because the game core designs were too flawed, and sometimes because the game audience couldn't get broader than a small niche.
In 2014, most hardcore gamers consider the industry is essentially about FPS and MMORPG. With SC2013, EA wanted to take that in consideration with their online thing but it failed. I still believe, creative games can succeed in 2014 and minecraft is probably an excellent example of that.
Maybe an interesting idea could be to allow the player to walk by himself in his city and even drive in it, a bit like in GTA. I remember a mod in CIM1 allowing to somehow do this. Of course the streetview will never be as detailed as in GTA V, but even if it isn't, Minecraft has proven it can work.