Nah, I wouldn't like that, character reveals are super hype, although NRS has never been that good at it. Ermac was revealed on Noob's trailer, and Sindel and Jade on a magazine. I think Killer Frost and Ares didn't get properly revealed either. I hope this time they give each character it's own trailer.
Still, I would love to have a real SECRET character this time around, not just unblockable, but really secret, something that gets discovered weeks (or months) after release. I remember when the survival mode for MKSM was found, that shit was so hype.
And regarding DLC, at least with NRS, it doesn't work that different from their previous games. Since MK3 most of their games have had expansions, UMK3/MKT/MKG/MKTE/MKU, now instead of being released as a new game or as a console exclusive with extra content, you get to buy it as an add-on.