Yep, gruesome as it was and disheartening to see it, putting that at the top of this chapter was a good one by the production staff - it really grabs the attention, especially to anime viewers who hasn't played the game. What better way to bitch slap the viewer that you ain't seeing just a loli-moe~ show than to start off with
One thing that did catch my attention was how they changed the game scene at Mion's uncle's toy shop. Overall it got the job done so I guess it doesn't really matter; especially since the anime isn't going onto Minagoroshi-hen.