You forget Jurina is the ace and face of SKE so it would make sense to think like that but Rikki was always helping out her team and the rest of SKE behind the scenes, you may not know it because the focus was hardly ever on her. She may have not been considered the de facto-leader like Takamina or a take charge like Sayaka or level-headed like Yukirin but she played a major part since she is a 1st gen. member.
Jurina is a strong girl, especially for someone so young but she's still just a kid and of course she'll need someone to talk to and of course who else will be there for her? It's pretty obvious that among Team S, they all rely on Masana, Rikki and Nishi; fans go as far and label them as the hidden pillars of SKE.
I know you don't mean any ill will by your comment but don't down-play Rikki's role because she was a very prominent figure, working behind the scenes.
Rikki was a patient and attentive leader and she will be missed.
gif cr: http://gifsofsakae48...st/28908337471/