The fights have been escalating for a while. In the first season, all the class cards were very powerful but they only had a basic animal intelligence. Cards like Caster might have been a clever animal and Berserker simultaneously was insanely strong and neigh invincible but they were still only bestial. In the second season, the enemies gained intelligence. Chloe was as powerful as Illya but she was extremely strategic and a bit more skilled than the original. Bazett did not technically have the power of a Servant but she had the skills and abilities which made her a Heroic Spirit class threat. Gilgamesh was not only vastly more powerful than the Servants that Illya’s gang faced before but on top of that, he was often one step ahead of the gang and had a Batman styled kit of tools and weapons. Every enemy was not only more powerful than the last but required everyone to think on their feet even more.
Angelica and Beatrice are the next logical step. They have the full power of a Servant beyond that of even Gilgamesh. The Servants they install are either equal or greater than The King of Heroes. They also both have extra tools on top of their Servant cards. The home turf advantage is just the cherry on top.
It is going to take much more than usual to beat these two and their even more powerful Master but that is what magical girl shows are all about. And despite the odd twists and turns, this is still a magical girl show at its core.