Put me in the camp of All FLock plus free choice oyster shell for the typical backyard flock, in typical backyard conditions, with typical backyard management.
As to pellet/crumble?
Pellet tends to be more expensive (takes additional machinery, processing time). It goes stale ever so slighly slower (less surface area exposed to oxygen), but you will never notice the difference, it works MUCH better in gravity feeders, particularly in high humidity conditions, and there's less waste - because chickens that spill crumble from the feeder are more likely to pick it up off the ground and eat it. That also means there is less waste to attract tasty bugs and unwanted rodents.
Crumble is (typically) cheaper. Its the same feed (substantially - a few companies add an insignificant amount of additional fat or oil to help the crumble stay together when peletized). Its problems with being scattered and lost (thus waste) can be relatively easily overcome by serving it as wet mash or fermented feed. But it really does not work in gravity feeders.
I feed crumble. As an oatmeal-like consistency wet mash. Loss amounts with dry crumble are usually reported as being between 2-6%. Assuming 5%, that makes a $20 bag of crumble the same value as an equally weighted bag of $21 Pellet. Yet there's a $1.50-$2.00 differential at the farm store.
/full disclosure - I get my crumble from the local mill, and pay less than $0.25/lb, the price differential for a bag of pellets, to be competative, is so tight the mill hasn't invested in the equipment - so when I am leaving property for days, and need to feed pellet for the gravity fed J feeders (4" sewage pipe and fittings), my costs go way up.
