Kusari is more akin to a feudal shoganate, which is the direct model used by the developers to create the governmental system. And it already its oppositional slots filled, both the Blood Dragons and the GC fight to replace the existing government. One with a true Emperor, and the other with a matriarch.
Rheinland is overflowing with political revolutionaries and every other kind of opposition under the sun, and Bretonia operates in a monarchy. With that in mind citizens in Bretonia as a whole don't want their system of government to change too drastically, they like it, it works. And beyond that, it gives them a sense of national pride.
Liberty really is the only house lacking a proper political movement bent on radical change and redistribution of power.
I think this points out why Liberty is a good choice, except the explanation for Kusari. I don't think that Kusari has no room left for another revolutionary movement but I do think that factions like the Hogosha simply wouldn't let that happen as the LRF's idea would overthrow the society's system entirely. Think about why there is no pirate faction like the LR or the Buccaneers in Kusari.
Now, back to Liberty. I like the concept of the LRF. You compare it a lot to the Red Faction Army that was active in Germany during the 70s. But that's the point where some problems arise. The RAF tried to achieve its goals by kidnapping or murdering high ranking members of government structures or the economy. How do you roleplay that? I imagine to see those things happen planetside or on stations, not in open space unless you regurlarly organize events with the faction leaders of the Big Three. That would surely offer excellent RP, ingame as well as on the forums (just imagine a LPI Swat wing that tries to free hostages from the LRF). But you can hardly roleplay it in the daily routines. Liberty has enough pirating factions already, so what are you going to do in the meantime? And where could you keep hostages? I don't believe that the Zoners would be very fond of LPI squads breaking down freeport doors.
The idea is quite good. But it's damn difficult to roleplay it in a game that only offers space as an environment.
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