Hm. True, but I think the way PMK is structured she should live.
If anything there are many "counters/contrasts" in terms of characters...
Tetsu/Suzu, Hijikata/Yoshida, Akesato/Ayu/Susumu...
If the mangaka is being deliberate in these contrasts (Which I think she is), I would probably guess that Akesato would live. Of course, it might be quite a lonely life watching everyone die, but thematically I would accept it as part of a balanced end to the entire series.
Then again, I might be presuming too much on part of the mangaka...