Having flown in 13B, 19B and now 24B there are pro's and con's for all of those seats.
13B in Emerald City is nice, upfront where meals gets served first. Its more of a private mini cabin, but not as mini as Rows 24/25. Also closer to the J onboard lounge.
19B which is smack bang in the middle of everything, just a standard J seat IMO. Meals gets served halfway but in the middle of the larger of three cabins felt it wasn't as private.
24B right at the back, exit row is nice, and felt extremely open, spacious and airy. Downside is the meals were served last and we waited forever, well it felt that way. It was far away from the bathroom and when meal service is in progress the trolleys can block both aisle access. I was directed by a purser to just use the Y+ toilet and I felt the stares from the Y+ folks.
Personally 11-13 is probably has the most pro's ..... and then I would probably go for row 24 next as its more private and felt much more spacious, then anything else in the main J cabin.