Could have done better
The key to this movie I think is about two things:
1) Sex appeal of the actresses
2) Making skinny girls beating men believable
First of all the blonde Kristen Stewart was not as attractive as I imagined. I think that makes the first impression of the movie a bit off. If Kristen Stewart could not look any better then maybe they should have used Naomi Scott as the honey trap and Kristen as the muscle. The bewitching power of the girls is the main reason to use female agents, even the movie says so.
Secondly, it showed nothing special about the fighting skills of these girls. The fighting sequences should have been designed a lot better and either to have the girls showing some slick moves (The matrix would have been a weird movie if not for the fighting sequences) or let them using small and light weapons designed for girls, for example poison needles or knives, in most hand to hand combats.
Sabina drinking on the job is a bit of "How should we take these girls seriously" moment. It is not like she was sipping drink to blend in, instead she was gulping down because she could not help it.
They could have shown more about the characters of the girls, have certain vice or some ways of dealing with the stress of the job. For example male agents such as 007 are usually extravagant and promiscuous because they might not live to see another day.
Anyway, the movie is not properly done. Elizabeth Banks did a very average job as a director.