More voices are a pretty cost-inefficient thing to implement and I understand if they don't go overboard with it. I would love some more voices, too though. The only good thing about the MC VA is that we only speak some a very limited amount of lines in contrast to say the companions.
I'm hoping for a good middle ground 3-4 VA for every sex seems about right in regards to cost-benefit.
I would be happy with a total of 4 voices per gender so long as they are fairly distinct from one another (right now the two female voices are too similar)
and yeah your character as of yet doesn't have as many lines as your companions, but if I have to listen to my character repeat the same 5-10 lines as I move about and click on shit I'd like to have a wider choice of voice options to have to hear it in. (I'd LOVE to have a female voice with a Scottish accent)
Just like adding scarring options (something else I'd like to see) yeah it is gonna cost time and money, but imho if they can spend the time/money making sure every race has it's own style of undergarments (something you only see if you decide to strip your character naked) then they can spend a little time and money on a few extra voices...