When Xi was picked, he was picked for the same reasons that Putin was picked - they looked like mild centrist candidates (ironic) Over the last decade, Xi hss focused a lot more on gaining authoritarian control over the party, the military, and the economy - using the law, and power plays. This has taken a lot of power from both the Capitalists, and the princelings.
Ask Jack Ma if he is still happy with Xi.
The CCP is not a transparent governing body, by any means, but there is no second body of officials pulling strings. There is no need for a hidden government, as much of the CCP's dynamics is hidden anyway. Most public decision making is ceremonial, with decisions being made in advance, and opposition being rare.
Xi was picked for succession by his predecessor, Hu.