Here's the thing for me, I think expertise dice are not bringing out the theme or flavour of the Fighter particularly well. As a master of arms and armour, it doesn't really matter what equipment the Fighter picks, because expertise dice outweigh any damage benefit from a heavy weapon, and there are no maneuvers, yet, that require a polearm (like a sweep) or a bludgeoning weapon (like a dazing attack). I am no fan of AEDU, but at least the powers were interesting, even if I didn't like the resource management style.
Expertise dice also fail dismally to bring out any feeling or theme of the Rogue. Part of this is because they are sticking to the rigid progression, and part of this is because the dice themselves limit maneuver design - things that only need one dice need to involve the size of the dice in some way, and because the dice get quite large you have to seriously limit what bonuses can be applied to, to keep flattened math (though they are failing at this already with some maneuvers).
Finally, the monk, I think, has actually done a good job with them. Why is that? Simply because the monk always had an ascending dice mechanic, which was unarmed damage. Notably here, they've not based unarmed damage off of your expertise dice size, which is a shame, because your flurry of blows attacks can be d8 or d10 when your main attack is at d6 - a little jarring. They've also got multiple dice maneuvers, which don't necessarily need to worry about how large the dice are because the number of available dice follows a certain progression. Unite the unarmed damage with the ability to spend dice for other effects and I think the monk might actually suit expertise dice - it brings out the style, theme and flavour quite nicely.
So my conclusion is that the mechanic has finally found a home, and perhaps now we can try something different for Fighters and Rogues please?