As Yensid already said, there are 17 new characters, not 17 animatronics in total. You've also got the returning characters including Tiana, Naveen, Louis, Mama Odie, Charlotte, Big Daddy LeBouf, Eudora, the King and Queen and Naveen's little brother. And a number of these characters (both returning and new) will also get multiple copies throughout the ride. Especially the main trio of Tiana, Naveen and Louis. I expect they alone will probably have at least 3-4 figures each. The animal figures seen in the concept art I believe were all confirmed to be part of the 17 new ones. I don't believe any are reskins of Splash figures.
That said, I was also told that they would be reusing the America Sings figures as well (WDW as well I assume, at least the ones that we ended up getting copies of). They seem to be keeping this a bit quiet. But in one of the pieces of art, you can spot the old possums hanging from the ceiling as a shadowy silhouette. A lot of these figures would be fairly straightforward to insert into the new ride with relatively minor changes (maybe some different clothing here and there).
I don't know the exact amount of animatronics the ride will have. But the basic gist is that fans of rides with large AA populations should be happy about that part. I was initially very concerned that this would be another empty ride with maybe a dozen or so AA's and wall to wall video screens. But I was assured that this wouldn't be the case and that it would be a classic AA-heavy experience, the likes of which they haven't done in decades. We'll see, though the pieces of artwork do contain hints that this claim is accurate. Not that there won't be any screens, but it seems like they're going to be used in a more tasteful and supplementary "effects" sort of way rather than in place of physical scenery/characters. I was even told that the AA faces would be mechanical, not projected.