If he's going on LTIR they are only paying 20% anyways

Eaves' health kept him out of all but seven games last year, and they waived him in February.

Anaheim might be happy to add Ceci. They have three established top four defensemen, and a fourth one could help their season go better. Maybe under a different coach/system, he finds his defensive game, and becomes a valuable hockey player. Of course, he could do that in Toronto, as well. Probably more easily, given the kind of role he's likely to end up in.

In light of Dermott's expected rehabilitation to run through December, is trading Ceci such a good idea?

Not to mention suggesting a guy who played an average of 17:18 a night last season is ready to jump to a top pairing role playing 23 minutes a night with Rielly is probably not a safe assumption.