This is something I'm interested in and hope will be elaborated on in the future. Why does he want a utopia? Does he just want to rule his own country? Is he an idealist deep down? The latter might be possible given his connection with Ivankov, a revolutionary.
Croc probably had a past both similar to Kuma's and to Dragon's.
Grew up in a kingdom whose monarch was dumb and corrupt, and because of his inaction and/or want to please the CDs, the state's prosperity dwindled away and the civilians were thrust into a life of misery and war. Croc probably thought he'd have made a better job as the king, so it became his plan to reach that status one day.
Croc then crossed paths with Dragon and Iva, but whereas the former had long-term schemes just like Croc, Dragon was also too passive, which was the opposite of how Croc operated, building networks wherever he went, looking for a con, a way to come out on top. Iva, on the other hand, is just a hedonist; the perfect right-hand man to a strategist who does nothing for entire decades, but useless to a man of action like Croc.
Croc, Dragon, BB, Imu are all sides of the same coin.
Croc wants to replace the WG with his own vision.
Dragon wants to cleanse the WG of the corruption and evil represented by the CDs and the man in the shadows.
BB wants to destroy the WG and impose global chaos.
Imu's reign is the dystopia that replaced the AK, the last historical utopia in the OP world.