In any case, long rests resetting everything is at the core of the problem. All or nothing nature of them makes it really tricky to balance. It sorta works if you use them to bookmark the narrative "chapters", like gritty rests that are extended downtime at the end of an adventure arc, but sometimes that does not flow so neatly either.
Rests restoring things more incrementally would be in a lot of ways be much better, and then we would not need to have two types of rests either. But with so many separate things and how spell slots work easy and simple incremental restoration is a bit awkward to implement. It would be easier if characters had just hit points, spell points, and, eh, prowess points (for martial powers and things) and those would be the only attritional resources to track and then a rest would restore some increment of them.