Agree about it being your car, so make it what you want. My 73 was the same color, like you I didn't hate it but definitely didn't love it therefore it had to go. If I was doing the car to resell, then I might have retained the Basin blue (probably not, but...). If the car was a survivor or even a numbers matching car, I "might" retain the color, however since none of these conditions exist, I would absolutely change the color. I think you know the right answer as you described the gray as a color you "love". Better to have a car you look at and love virtually every respect than one you like most everything but the one thing every one sees first and foremost. You will constantly be telling people how you "like' the blue but would rather have it in gray. At this point in time, so long as the paint job doesn't suck, value should not be an issue.
But again, your car, your money.
