It's weird how Akechi is pretty much the only one who's personalities have merged into one. With everyone else, their past life seem to take over.
Not too sure about that. He might be willing to look forward instead of clinging to the past (understandable, really), but he also sees himself as the guy from the Sengoku Jidai.
Moreover, he lampshaded something very important here: the historical Akechi was indeed unusually devoted to his wife, Tsumaki Hiroko. No concubines, no lovers, no cheating. When his fiance got smallpox (marking her entire body), her father offered another daughter to Akeuchi, but he refused, insisting that the only woman he wanted to marry was Hiroko. And when enemies conquered the castle where they lived, Akechi carried his pregnant wife on his back in his escape.
That is, modern Akechi being a hopeless romantic that will do anything for the woman he loves is very in-character for the historical Akechi too.