So just curious. Now that we know a bit more about Sword & Shield, who still thinks the Grass Type Gym is the 1st Gym we'll be challenging? Because I have a feeling it won't be.
It's 100% the second gym. Milo's Eldegoss is allegedly level 19, which is solidly in second-gym range. The only games I can remember where where the second gym's ace isn't around level 20 are X and Y, where there's about a third of the region between the first and second gyms.