Yeah, that's the way I see it. I still think Urien's a Bonus Boss that'll get added to the actual roster down the road, and that Juri will be on the default roster instead (She's way too popular to just ditch like that). But that's how I think they meant to organize it, too.
I think the game launching with 16 characters is kind of a misnomer. I believe it'll launch with more than 16 but buying the game alone will only give you access to those 16 initially. I think it's very likely we will get more in the form of unplayable bosses, unplayable secret bosses, pre-order bonus characters, or day 1 DLC. I think Capcom may be uneasy in just having a ton of characters available to buy Day 1 after the SFxT backlash but I'd be surprised if, say, Akuma wasn't a preorder bonus or day 1 DLC.