I am not sure why the notion of Luigi, Toon Link, Marth, Rosalina, and Lucario possibly being on the starter roster is so incomprehensible.
Yeah, Marth, Luigi, Rosalina and Lucario can easily go as starters as far as I see it, in fact I think Marth, Luigi and Rosalina are better fit as starters, where as Lucario can go both ways easily. Toon Link is a bit weird, but eh. It's most likely just shaking the starting roster up, I can't see any reason they'd reveal a mix of starters and unlockables at the same time, that'll just lead to a lot of confusion, especially for people who go on the site post-release to see that and unlockable is near the bottom of the page between two starters. That's just unnecessary confusion, especially for characters like Marth, Lucario and Rosalina who weren't revealed to tie into anything specific, so why didn't they just reveal starters on those dates instead?
The starting/unlockable relation has always been shaken up. In Melee C. Falcon and Ness weren't unlockables, I don't see how that change is any different from throwing Marth, Luigi, Lucario and Toon Link to starter position, not to mention they were made unlockable again in Brawl. Furthermore, Brawl also threw Jigglypuff off the sacred "1st character to be unlocked" position, probably the only real "pattern" to unlockables that was prior to that. It's just change, I don't see why it's so hard to understand that they're likely starters.