I'll admit rack pulls are good for back and lat development.
What it boils down to is that you'll just have to figure out what works for you. Stick with something long enough to tell if it works, make little tweaks and changes here and there and log your training and see what happens. It's going to take some time, of course. From what I've read here it seems all the bigger pullers go about their training in vastly different ways anyway. Find stuff you like, tweak it to suit your needs and make it your own.
Edit: congrats
@jaymaximus on the four plate pull! Five minutes is about all you can really hope for before you convince yourself it's really not that heavy and the next plate milestone is what you really need. At least it keeps us motivated.