There are 2 types of silent protagonist. There's the Baldur's Gate Dragon Age Origins type silent protagonist where you do actually engage in conversation with NPCs and party members it's just that your character has no VA, just text options. Then there's the silent protagonist that is mute both vocally and textually (is that a word?).
I'm fine with the former, but I don't really care for the latter if the game has an actual story. If it's just as pure game with basically no story then it doesn't matter.
So, I prefer a protagonist with a voice whether that be a text only voice or an actual voice is less important, but of the two I would normally prefer the actual voice. Having said that, in some ways the Dragon Age series lost its variety with introducing voice acting for it's main character. But it got it back by not worrying too much about giving different race choices totally different voices in Inquisition. Conversation choices are much better when you know more completely what you're going to say to your friends / enemies before you say it. Having an icon and 2 word phrase prompt isn't as good.
“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
"When the power of love overcomes the love of power, the world will know peace."
Jimi Hendrix







