There is always Troi or Crusher taking over the computer voice duties. Its going to be weird not having Majel voicing the computer and not going to be part of the new future of trek
That's not a bad idea. I think Marina Sirtis could make a great future Enterprise voice.
Nichelle Nichols would sound really good also, though maybe a bit too low in pitch at times for a computer voice. It could always be subtly modulated though.