I'm not so sure if all these developments weigh on him as heavily as you think.
They will surely make him sad, but when we consider Kaneki & Akira, I doubt their relationship developed to such an extent that it'll leave a whole in Kaneki's heart. Akira neither looks like a person capable of having intimate relationships with the first and best person assigned to her care...
Not saying it won't hurt, but in the grand scheme of things Akira's death will be easily accepted by Kaneki. Because with her death, that would be a person less to face for Kaneki. Since he doesn't know the progress on Rue he must be convinced that facing her is inevitable, since she's initially a CCG investigator out to exterminate ghouls and he knows her well enough to know he won't be able to change her mind that easily.
However current development with Amon's appearance and Akira's reckless act, might hint at a possible bridge that can be made between them. Akira should be able to understand ghouls better after what she just did. Imo she made the decision to save a ghoul, which is considered treason automatically. The only ones she can depend on now are Amon & Seidou & later on Kaneki depending on how things turn out on Rue.