Nose-time and fin size

I have read the fin primer and it is great stuff, but I have a more specific question: I am looking to increase my nose-time and wondering how a new fin will effect that. Right now I do move around on the board (not quite cross-stepping yet) but am only able to get way up to the nose on very rare occassions and have never gotten any toes off! I have a 8" dolphin single (stock fin for the board) on an NSP 9'2" epoxy with a slight single to double concave, soft rails, and low rocker. The fin is three-quarters of the way to the back of the box. I am 160lbs (74kg) and surf an east coast (US) beachbreak usually knee to waist high. I want to keep the looseness and low-drag (I can paddle and catch almost anything) but need to know if I can get more hang-time (and any other considerations) before I invest in a new fin. Any comments on sizes and shapes for me? Thanks!