A huge improvement. Mulgrew was about as convincing as Patrick Stewart was in his fight scenes. Sorry, but those two would get their butts kicked in a fight against pretty much anyone in the universe. And it would be nice not to have to listen to Mulgrew's voice. ugh...like a cat scratching on a chalkboard.
Wasn't Linda Hamiltons voice also rather damaged by her smoking habit? Granted, from what I remember it's more scratchy rather than that weird gummy bear squeak Mulgrew has, but I'm not sure it would have been that much of an improvement.