Despite Umineko has a good story and good characters overall it presents a really poor mystery that ruins some of the characters that were so well built in the first chapters.

I can get behind the killer's theory and explanation, but i have a problem with the accomplices changing in each chapter. I get Nanjo, Genji and Kumasawa are always accomplices and have a full devotion to fullfil Yasu's orders, but the rest of the characters being or not accomplices on some of the chapters seems like an easy route to explain all the mysteries present in the game.

Lets take chapter 1 for example. After the 1st twilight; all the people alive but Natsuhi, Battler, George and Jessica are culprits. Chapter 2 its the same, with only the cousins being innocent after the 1st twilight. Chapter 4 its even worse, where all the characters BUT Battler are involved in the murders. It makes the mystery unfair to the player because it constantly puts them on an Orient Express situation in each chapter where everyone or almost everyone is the killer.

I get most of the characters are just horrible people that could be made into accomplices by the temptation of money, but i dont see, lets say, Gohda, agreeing to act as if he just saw some rabbit-girls murder all the family in ch4 and make a flawless performance out of it in front of the cousins. I cant see Kyrie agreeing to this plan either as clever as she is. Eva and Hideyoshi being involved in ch1 seems also quite lame to me.

Lets not forget some of the accomplices saw how other accomplices were killed, and they continued to act under the orders of the killer thinking 'oh well, for sure they arent gonna kill me!!!' I cant see a world where Rosa, Gohda or Kyrie really thought this and continued to act under Yasu's orders obediently.

Idk how to explain it, but it feels as if Ryu wrote the whole chapter and only then decided who the accomplices would be in order for the murders to have a human explanation.

Ironically, the chapter with the less accomplices present, chapter 3, its the one where they straight up tell you Eva is the killer in a really poor mystery where everyone but her have an aliby in almost all the murders of the story.
The characters dont even act like themselves on ch3. Kyrie and Rudolph confronting Hideyoshi ALONE while he has A GUN doesnt make sense. But its even less understandable when you read ch7's tea party and discover that Hideyoshi DOESNT EVEN KNOW HOW TO RECHARGE THOSE TYPE OF GUNS WHILE KYRIE AND RUDOLPH DO!!! So him killing both of them its just convenient for the chapter to work.
Krauss and Natsuhi drinking from the coffee Eva prepared for them its also so bad executed and convenient for the story to continue lmao.

Overall, yeah, an interesting story and good written characters, but the mystery is bad executed, ruining the good writing of the characters in favor of an easy way out for the story to continue. I think it wouldnt be imposible to create diverse mysteries where not more than half the cast has to be involved for them to work.