another question: when asking about a sector I am interested in and an example of a recent deal -- do I need to speak about myself and why that sector deal in particular stands out to me?
I do not think it is a requirement for your answer to be very "you-focused" in the sense that you talk at length about why you are more interested in a sector than most other people are, but I do think it is advisable to at least link it with one of your experiences to illustrate your motivations. What I would say is a requirement is to explain why the sector you have chosen is more interesting to you than other sectors, which is the "sector-focused" part of the answer: in essence, you will be picking out and analysing features of that sector and the work lawyers do in that sector that is more appealing to you than features/work in other sectors.
Nonetheless, in many cases this will not suffice as such a discussion can remain a bit too abstract and arguably will not satisfy the "Show, don't tell" rule in application writing - the idea that you need to look to evidence the veracity of your claims. Arguably, the best way of doing so is to make use of concrete examples of your experiences illustrate your broader points.