Some things to remember:
Collaboration
Socialization
Class Size
Student ability to sit next to others
Focus
This seating arrangement has a focus on collaboration. With groups of 4 each student could have different thoughts to bring forth to their peers. Students are able to socialize with more of their classmates throughout the day, while also being able to do independent works
This seating arrangement is better for a lecture or a presentation to the class. The purpose of this seating arrangement is to focus on who is at the front of the class. All students will be able to focus and see the front of the board. But would be difficult to colloborate with peers.
With pairs students are able to work alone or with someone else. When needed students are able to collaborate. Although the only negative to this seating arrangement, is how students will have less interactions with their peers.
This seating arrangement is great for long term group projects, or teaching a comprehensive topic that could require more collaboration. This is also good for work stations, student are able to rotate around the classroom.
This classroom arrangement can be used for two main purposes. One way would be that the teacher can determine different amount of rows and how many students are in each. Another would be that all the desks face slightly towards the center of the room, where a white board could be. The only downside is that students would be looking at backs, and it would be harder to collaborate.