Assuming it isn't in the game at launch (which I hope it is), I wouldn't see it as a paid DLC, but more in line with what Disco Elysium did, i.e. simply add it down the line in a definitive edition (free update for those who had the original), a good reason to re-sell the game at full value rather than discounted.
That said, I really hope we have voiced protagonist for Custom Characters AT LAUNCH (with the option to turn that off for those who don't like it).
Also waiting for the day a game like this gives you the tools to pre-record and add your own voice (he he).
