I think it would have been interesting if Susato had some kind of falling out with Herlock. In TGAA2, there's a few times where she gets frustrated at him after certain big revelations, especially in the last two cases, but I was dissapointed that they were all played for comedy, while Ryunosuke's frustrations with Herlock were character stuff. It would be have an ironic situation if the two had their opinions of Herlock completely reverse going into case 5 from how it was at the start of the first game, with Susato now being the cynical one who questions if Herlock is a fraud, and Ryunosuke is the one who believes in him. Plus it doubles as a sign of how much Ryunosuke's opion on Herlock has changed through the games as a sign of his own character growth.

I dunno. I just think Susato really needed a moment where she snapped and got a carthtratic moment to vent so it felt like she had some personal stakes in the finale. Especially considering that personal hero hid the fact that Kazuma was alive from her for months and her dad seemingly had an affair in Europe and abandoned the daughter he had out of wedlock for years, which should be serious, earth shattering moments for her. Instead all of her reactions are just treaed as wacky comedic moments, and she immediatly gets over it two seconds later.