Yeah I wouldn't say it was rushed. With Isley and Luciela dead is was only a matter of time before Riful got killed off. Hell I expected Alicia/Beth to kill her off. I guess Yagi went this way so that Riful could give some commentary for Priscilla during the A/B fight and to reestablish Priscilla at Omnigod tier.
Only thing I guess I was shocked by was A/B getting killed off since I figured they would be the orgs last line of defense and not Raki. Since we know about the DoD on the mainland, Yagi can now start to establish that part of the story. Now if he planned to kill A/B, R&D just so that he can get the Clare and Priscilla rematch and finish the manga, then you can say he's rushing shit.