This is all well and good but how does any of the new mechanics shown so far benefit "tall" play over "wide" play, currently due to how dev cost increases past 20 dev the optimum strategy is just to blob as much as possible but dev ever province to at least 20. Monuments are a good reason to play wide to get all the bonuses from them, setting up an optimum trade network demands that you play wide, goods like coal and the soon to be added cloves are great reasons to blob and unless paradox changes something significant playing wide will always be the optimum way to play.
However what I think paradox really misses is the fact that even if playing tall was the best way to play nobody would still do it because it's extremely boring, eu4 is a war game, there isn't anything to do at peacetime except prepare for the next war. So yeah trying to encourage playing tall is a complete waste of time imo.