The new coaster is starting to sound to me a lot like Barnstormer, which will be about 200 yards from it. What's the point?
I'd call it more of a combination of Barnstomer, Pirates of the Caribbean and a typical Disney dark ride. Barnstomer isn't particularly friendly to adults. When you get beyond some of the theming, it's really just a small-scale steel coaster. It is also quite short.
From what I've heard, the mine ride would be a fairly unique design. Perhaps calling it a dark ride on steroids is a fair description.
If you think Disney already has too many dark rides, then this probably won't be your cup of tea. And it certainly is no scream-your-head-off thrill ride. But it could end up being a nice combination of the two, with the appropriate intensity level for Fantasyland.