This post feels eerily similar to one of my early posts in the 5e concept test back in late ‘12 or perhaps ‘13!
The thrust of that post was that balancing a game around the zoomed out Adventuring Day rather than the site of the Encounter was begging for a fraught combat engine where (a) GM intervention and exceptional cognitive load was going to be a profound feature of play (given the intricate features of modern D&D combat), (b) therefore play would progressively (as levels piled and Long Rest classes through-put and spike capability on recharge became increasingly significant) feature an arms race over the Long Rest recharge (that GMs who wish to control pacing can trivially do at their discretion by deploying offscreen assets or unrevealed backstory), (c) and therefore it’s going to pose problems to surmount (via more GM intervention) for both Story Now play (where everyone, including the GM, can play aggressively, just let things unfold, and can play to find out what happens) and also challenge-based Gamist play (where the engine does its work seemlessly and predictably, for the GM, at the encounter-level…without intervention…eg x difficulty is reliably x difficulty fight-in and fight-out…so both sides can play accelerator to the floor and feel good with the competitive integrity of play).
And my second critique was that class resource scheduling not being unified is going to obviously exacerbate this (requiring more GM intervention in tailoring, pacing, and the temptation of fudging…and increased related cognitive burden on the GM). But that ship had set sail so that critique was just an aside.
EDIT - As you might imagine, that offering was not received well back then!
Yeah, sigh, I remember making EXACTLY the same comments. I even wrote it all up in detail and handed it to the developers (I assume they basically didn't read any of their email/comments, they just pretended to want them). There were quite a few of us doing that on the WotC boards, with varying details, but generally in the same vein. There is a real REASON why something A/E/D/U-like is desirable! Honestly I've broken with that paradigm in my own design at this point, but the key details remain, there are substantial enconter-based resources that are held pretty much equally by all classes and builds of character. You all go into every fight, or other situation, with resources at the ready and roughly in the same quantity as everyone else (there are also daily resources, again everyone has the same).
There are certainly some things to tweak in a system like 4e, like how swingy combats are, and the exact ratios of daily vs encounter resources. I think the daily ones are actually a useful tool, if you reduce them too much then you lose some ways to easily model stress on the party. Many sorts of games don't need that, but IMHO it actually works pretty well for FRPGs of the D&D ilk. Too much and the GM gets burdened with certain pressures (trying to subvert a tendency to stop and rest all the time for example). Too little and basically every fight has only plot significance, or else pure hazard value on its own.
This is a major part of the reasoning for my own design decisions. HoML has, basically, ONE resource, power points, that underlies all the others (you can invoke riders using them, emulating daily/encounter powers, and they also work as both HS and AP effectively). Tweaking pacing becomes silly easy. How many of these points do you start with after a complete reset (Recovery) and how many do you get back after every (short) rest. The more you go with the later, the further you move towards pure encounter resources, so its pretty darn easy to tweak! Honestly, I currently have the limits set at you start with 8 points and get one back after every rest. Presumably you're going to use 2-4 points in an average fight and the day can then go from 2 to 5 or 6 combats depending on difficulty, etc. and you can then throw in your challenges and such to arrive at whatever the total encounters per day expectation should be. Tweaking the starting number changes the expected day length, and tweaking the recovery number shifts you more into pure encounter mode (and presumably you then cut the starting number a bit, perhaps).
You can also do fun stuff with that design. Like Consumables are 'frozen power', you can spend a point, carry out a ritual, and 'embody' its effect in a consumable. That lowers your available power points by one until its used or discarded. Planning is now fun and interesting! It is pretty thematic too, the Alchemist is pretty serious when he says "and I'll need a vial of your blood..." lol.