Speaking in terms of the vantage point of just the original, Chrono Trigger, I don't even think Schala's fate was any more important of a loose thread to tie up than other things like Robo's. We don't see Schala vanish, we just last see her slumped over in the Ocean Palace as it's going down. And all that's said about her is that 'no one has seen her since.' So until Chrono Cross (and RD) expounded upon what happened to her, I think it was reasonable for me to just assume she perished in the palace collapsing, nothing more. Which would mean that to me, there were NO important loose ends that needed addressing. Isn't that at least a valid thought?
I understand that things change as series continue - all I'm saying is if they could make a second entry based on one unknown eventuality (Schala) that might not even be noteworthy to some players of CT, they could certainly make a third from some other loose thread from CC that we don't think much of YET merely because nothing's been made of it yet. I hope I'm explaining my thoughts well enough lol.
I guess overall, I thought that CT was complete in and of itself, but CC opened it wide up and left it vulnerable while at the same time making it so complicated that it was hard for me to grasp it, all happening because of one loose thread that I didn't even agree was an important or existing loose thread in the first place. So I'd either have liked it to just stay one game, or I'd like a 3rd, to help me grasp the 2nd better. But just leaving it at 2 games, and hard to grasp, leaves me feeling a bit empty about the whole thing.... Even for those who don't feel the same way, do you at least understand what I mean?
Anyway, that's just how I feel. Nothing more than that.