Just some notes from the top of my head which I remember from A-Level.
This is all a bit messy but I hope it gives you a few ideas of points you can include in your essay.
Some strengths are that it shows that non-cognitive language IS meaningful. It is supported by Hare's 'bliks', the idea that even if someone cannot be verified, it is still meaningful if it has an impact on someone. The idea that language operates according to rules depending on the context is true. For example, sporting terminology or **** may not make sense outside of it's context and it would be wrong for, for example, someone who has nothing to do with football to say that the off-side rule is stupid. So it makes sense to apply this to religion as well. The context of the Christian God needs to be understood within Christian context and can't be refuted by outsiders.
However, some weakness are that language games and forms of life can be used to protect dangerous ideologies if we take the idea that all claims are equally valid and another form of life can't refute another one. For example, if a Nazi said all Jewish people are evil, a non-Nazi couldn't say this is bad since they don't belong to the Nazi form of life. Language games makes it seem impossible to have meaningful dialogues between societies and religions. It would also rule out discussions concerning science and religion...
Yet, people belong to multiple forms of life. There are religious scientists, so are they allowed to be critical of religion in a scientific way, or do they need to keep science out of their religious life. Furthermore, the idea that people cannot understand other forms of life is wrong. For example, I am an atheist, yet I study Christianity and understand Christian concepts.