Seriously, I do not understand why any DM needs to worry about "encounter based design".If a player has invested in an Encounter power, they presumably want a power that works every encounter, which means the DM either has to worry about encounter based design or result in the player having no idea what the power level really is. Which frankly makes them a reasonably bad idea.
Because making sure the DM is on the same page as the Players when it comes to expectations is important.
Daily powers can have the same issue, but people tend to be on the same page when it comes to knowing you get a long rest every 24 hours, there is no shared consensus about how often you should be able to have a short rest.
Some spells might also have greater (for at-will spells) or lesser (for daily spells) effects that a character who knows the at-will spell or has prepared the daily spell could use in a fight and regain after taking a short rest.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.