Seriously: The old system had a lot of design flaws which the CS-system doesn't have to the same degree. I see the design as being superior, though needing further refinements in how it functions.
Where I see a serious problem is in the policies of Paradox: If you only have development and government ranks when you have the DLC, you are excluding a huge chunk of the core game from the people without the expansion which I find unfortunate, particularly when it comes to future design of DLCs and the more ethical side of "pay to win". The previous DLCs were mostly optional and less gamechanging features. I can see the reason for not wanting redesigned and somewhat unfinished features in the core game, But I don't like the use of the paid DLC as the cut-off. A beta patch is a much better option, a further division of content in making DLCs into content-packs with several DLC-toggles of which some are free or, by far the best option, you can make an ingame menu of game features you want to toggle on or off when the massive redesigns happen if that is the reason.
As for "too many monarch point sinks", I would be more inclined to further specify the needs. For diplomatic and administrative, you can always find something constructive to use it on, Ie: Coring, increasing stability, reducing inflation and reducing war exhaustion, peace deal brokering, annexing subjects or culture converting. Military points, on the other hand, could be wasted in the past since you usually run out of money for buildings before you run out of mil points, not always needed to beat down rebel factions and other sinks may be unavailable according to your choices. Where I see the problem is the classic money sink problem: You can now easier get to use your money on buildings, but over time a lot of the endvalue of the buildings are... More money! The monarch points you need to use for having buildings as moneysinks now starts at zero, but will explode as you need to develop provinces to unlock more building slots. In the end, the problem of too few money sinks compared to monarch point sinks is still in the game and it is part of the reason why development should not be the end of changes to the game. Development gives a further potential military point sink, which is good, but what is needed is a way to make money worth something other than more money or military might since military might rarely is the limiting factor compared to the diplomatic point and/or administrative point limited blobbing if you know how to handle the diplomatic game. Right now money is just a number, still, while monarch points are god, still. That is the problem of sinks: The games expansion mechanics (and therefore the absolutely most common goal of the game) is converging towards being only limited by monarch points as you blob, is the problem. How to fix that depends on the direction Paradox wants to take the game, but it may be a good idea to consider how to make other endgoals of the game more interesting or make money and what they can be used for, more effectual on the decission-making of the end-game.