It made them sound like the people living in a wild west culture
That’s newer canon and folks should obviously pick and choose as they want. But I’d argue that the frontier backdrop in HB:P goes against other sources. Various maps and timelines show that the Circinian worlds had been around since the Rim Worlds Republic. The SLDF used state-of-the-art military training facilities to organize 17 volunteer regiments on those worlds during the Amaris crisis. And the cover of J:FR depicts a downtown metropolis on Circinus. They’re not New Avalon, but neither are the Circinian worlds undeveloped, frontier planets.
As written in FM:P, what frontier remained on these worlds during the Succession Wars was economically exploited through a system of indentured servitude that developed into outright slavery over time. The model would be closer to the pre-Civil War US South than the US Wild West.
Frontier worlds would be the nearby Lothian League, where the population literally makes its bones hunting and trapping. Lots of Ron Swansons there.
Reading that book I don't get a mafia vibe, or a duplicitous vibe outside of what the Black Warriors do.
The Black Warriors are state-sanctioned pirates operating under false flags to maintain the government’s deniability. The were a model and trainers for the Shadow Divisions. Duplicity and organized crime is arguably inherent to the state, if not the society. Slavery is inherent to both, at least according to FM:P. Dunno why these elements were dropped in HB:P, especially when they were important to the evolution of the Blakists in the run-up to the Jihad and especially when other realms (Lothian League, Mica Majority, etc.) have had the Wild West frontier backdrop from the get-go.
So I guess I'm saying there feels like a disconnect between FM: Periphery and Handbook: Major Periphery States. At least to me.
I think you’re absolutely right. You just gotta decide what appeals more. And if in conflict, newer canon trumps older.