I think the loss of Yda and Papalymo was the downfall of the scions as an interesting group of characters. With them around we got a mildly entertaining dynamic and, most importantly, there was diversity of thought among them. Sure, Yda was the ditzy blonde comic relief but there was nothing wrong with having a "dumb one" around to think of things simplistically because that can prove to be valuable input. Now the scions are just geniuses 1 through 6 who agree on everything, and Estinien is left to fill in the non-genius spot but it doesn't quite work because he still has that "cool" image and ends up on the same page as everyone else anyway. I will never hate Lyse because even though she was a downgrade from Yda she still kept that less-thinking-more-doing rationale and it made for some entertaining moments in 4.0 like when she kicked the shit out of that Namazu. Also, her putting things simply was useful for communicating concepts to readers who couldn't follow along with Urianger's Shakespeare impression all the time. Now when the remaining scions try to put things simply for the reader it just feels like they're talking down to you.

Whoever our new friends end up being, granted that they ARE new, I hope we get at least one meathead who charges into action without thinking and either subverts the situation by showing that the solution was more simple than we thought or creates minor issues by doing so. Give a little bit of spice to our main cast! A bit of fun! Some whimsy!