Limited stamina works perfectly fine. Instead of having your stamina bar going down to 0 in a second, ala Skyrim when doing power-attacks, it would be a much bigger pool to begin with.
So as you do things that require stamina, you're able to regain most, while a tiny fraction goes into the damage side. The damage side of the bars should only be possible to fix through a combination of rest and eat (where quality thereof actually matters), but not required so often as to totally ruining the gameplay. If you choose to ignore it, you take the penalty by having little reserves to work from.
All the "cheap effect" like spells and potions, only work on the regen side of the bars, and it's completely up to the player how he wants to manage his reserves, which pretty much drain constantly at varying speeds depending on usage and circumstances. Low on stamina reserves? Gulp down potions for a quick "energy drink" (pretty much as in real life), but it has limited effect wrt time, and to regain fully you need to take more planned actions like resting.
So even if your stamina regains quickly after a power attack, if you're well rested beforehand, you may be able to deal out 20 power attacks instead of only 3 before falling under the required amount needed for the attack.