Hey
@KBanana I think your approach is good but potentially not always optimal. As I see it, it works well as long as the firm you are currently applying to excels in the three practice areas you have identified to a greater or at least equal extent as all the other firms you end up mentioning. If there is any other firm that seems to do better in those areas, this will raise the question like 'why should you not prefer them over us?'.
As such, I used a slightly more tailored approach. I would essentially repeat the underlying two or three motivations for why I was applying to this firm, and would then treat the two three points as
firm selection criteria. Then, I would list 2-3 firm that also scored well in every criterion. Since from the beginning these 2-3 criteria would have been selected to best apply to the firm in question, there would be no doubt in the recruiter's mind as to which is the ideal firm for me when they read my 'What other firms have you applied to' answer.
I have analysed this topic in a lot more depth in a recent post about this same question (although in the context of an interview). I have quoted it bellow, as exploring the deeper rationales may be useful to you: