They are all very different.
We considered Wilmington about 5 years ago and decided against it for 2 reason. The downtown truck traffic and the hurricane risk.
Asheville has a certain flavor to it - artsy and eclectic, and right in the middle of the mountains. We have friends who live down the road in Maggie Valley who love it - but it's a bit too isolated for us.
It's been a long time since I've been to Charlotte - but it seems to be more of a metro area, like a smaller Atlanta. Has the bigger city amenities and professional sports, etc.
VERY different areas. You really need to visit each to see which flavor you prefer