If forced against my will, I'd support voiced.
If forced against my will, I'd support muted.
The biggest problem that I have with the way Destiny does things is that while we technically have a voiceless protagonist (most of the time. I'm pretty sure that there were lines for the character in Destiny 1), what we actually ended up with is something else. While our actual PC doesn't speak, we're bonded to this little floating light that speaks for us in every single situation. It's not like our PC never speaks but has a dialogue wheel; this would allow our character to remain voiceless while also allowing the character to choose text responses that would fill in the character in the way that they want them to. Yet, we also don't just sit there silently while people deliver information and instruction to us; in every instance that I can recall where our character is spoken to, Ghost simply replies as though he speaks for us. It defeats the entire purpose of the whole "blank slate mute" that seems to be the typical goal of a game with a mute protagonist.