The biggest challenge at NCL security tends to be other passengers not knowing what they are doing, trying to take carrier bags full of various gels, liquids and other potions through security, not disposing of drinks etc. That was my experience on Wednesday. Even with those challenges it was still speedy.
Metro takes 35 minutes from Pelaw (my local station) and I had planned on catching the 09:19 service which would have got me to NCL at 09:54 for the 11:25 departure. Plenty of time, but my parents are old-school and always want me to leave far earlier than I would usually do. I ended up getting one of the peak Pelaw - South Gosforth metros and then what would have been the 09:07 service had I waited at Pelaw. Hence I was at the airport at 09:42 and was probably in the Aspire lounge by 09:50 even allowing for a manual check-in at the desk, aforementioned faffing at security, and a slalom around the Duty Free shop!
As for the £4 charge for the drop-off / pick-up point in front of the terminal that is daylight robbery at its finest.