I do have an extra GTX 980 windforce that I can install into the core (I was running planning to run SLI on my PC but I've been lazy and haven't taken the time to install the extra card and set it up properly).
And I do agree that 14" is the sweet spot for small laptops. When away from home, probably the hardest thing I play would be world of warships and world of tanks. I do play Battlefield 4 on my G750JZ , but that's when I'm connected to a good internet connection like at a relative's or friend's house.
The whole point of the Stealth and Core is so you have something compact and mobile when you are on the go, and when you go home, just plug in and play whatever triple-A title you have installed. But, hopefully Razer either updates the Blade 14 to be compatible with the Core or they release a new Blade that is compatible with the Core. The 12" screen was honestly the biggest turn off and what made me go meh when thinking about buying it. But with all this input, for now it looks like I'm leaning towards the Blade 14 unless Razer announces a new Blade that is compatible with the Core.
As of right now, I'm still saving up and probably won't have all the money until late April or May, so they still have time.