1. The fair comparison for At-Will resources is not Encounter and Daily resources, it's other At-Will resources. So a Wizards cantrips and rituals are the fair comparison, not their limited 2nd level spell slots.
I agree to this statement, but likely not the conclusion I suspect you're drawing.
The fact that movement is at-will and not per-day is not a good argument for nerfing it into uselessness.
The key point is that a fighter will need to make at least one "great jump" each day of adventuring. Or something like that.
If the movement rules can't give you that, then they're useless and the player turns to magic.
On the other hand, being able to do this more than maybe three times, the added value sharply declines. That is, if it isn't OP to let the fighter jump straight up once a day (Misty Step) then it likely isn't OP to let him repeat that.
I would MUCH rather have jump rules that reflect the reality of how the game is played, and what the average adventure asks heroes to do.
If you're concerned about the at-will-ness of movement, it's far preferable to institute a non-trivial but still manegable cost to this.
If the fighter can jump 30, 40 or more feet, but has to pay a Hit Dice each time, then the ability is effectively no longer at will.
(Not saying this is necessarily a good balanced solution. Trying to make an example here)
But (much) more importantly, the Fighter can now perform his duties without having to succumb to the D&D curse that is "everybody needs magic all the time".
And most important of all, you haven't wasted your time creating a Jump rule that in practice means "you can't make the jump, use Misty Step instead".