Im at PA now and at Principal Consultant rank (albeit a different practice to People and Talent). Don't worry too much about the sector alignment as you'll have plenty of opportunity to span multiple sectors. If you stick with Defence, you'll spend most of your time working remote in Bristol and nearby area.
Culture is decent enough - big enough company that the opportunities are challenging and CV-boosting - but small enough that you wont be lost in some giant machine and treated like a number. You'll get plenty of face time with the partners and given a lot of autonomy in your role.
I genuinely believe we offer a superior level of service to ACC and similar. (although we do charge more)
People and Talent is not the most heavily utilised practice but it is doing very well - your utilisation target will be 80% but this shouldnt be too challenging to meet. Make sure you do hit your bonus targets though - as the bonus is great. You'll be looking at around £15k in people and talent for a normal year at PC rank (although maybe someone else can correct me on that).
As for the bad points..... theres a massive push on business development at the moment which is often at odds with the culture of building lasting client relationships. I've recently seen more bad behaviours than in the past (i.e. selling at PC rank and only resourcing with a C with no support to maximise profit). It can often feel like PA dont know how to manage and grow a strategic account - some practices and partners are better at this than others however. My main complaint is that many of the clients are dull and the projects boring. Great for profit, but ive been here 4 years and never had a client or project that my friends or family have been interested in hearing about.
All in all - its a good culture. Would recommend.