I agree.   
Anyway, finished Cartagra. I think anyone who planed to read it should ignore all the other endings on their first playthrough and go straight to Kazuna's Normal End & True End because that is where the story becomes interesting. You can read the other endings if you want to collect CGs, and some of the Bad End is actually pretty good like Nana's Ending, but most of them aren't really worth it.    
Cartagra has good characters and I really liked Rin, Toji, and Takako for the part they played. MC role is quite useless though, I dunno how they could call him a detective and get all attached to him. He didn't do anything significance tbh, except fucking everything that has a pussy. Nana is obviously a better detective.   
In any case, this game made me hate and cursed InnoGrey deeply (for good reasons). lol Cartagra 7/10