I didn't like how overtly sexual it got in regards to Satsuki and her mom. There was a scene earlier in the series that was basically her mom getting her off and then when Satsuki was captured, her mom like... sexually spanked her? I get the idea that her mom is not really "human" anymore but ick. Made me feel uncomfortable. Also her right hand helper, Nui Harime? Hated her. Hated every second of her. Especially with the revelation that Ryuko is also made of life-fibers it makes her universe-breaking powers make even less sense.
I agree with you that I wasn't a fan of the Ragyo/Satsuki scene and it was better left out, but I had no issues with Nui. I thought she was great as a powerful but wacky sub-villain that wasn't meant to be taken too seriously, and seeing her finally get what she deserved was one of my favorite moments in the whole series. Hell, my normal aversion to gore didn't even kick in when she got "disarmed" because I was too busy laughing so hard.
Just my opinion though. I totally get why someone wouldn't be a fan of her character, and that's fine. ---