I would go for one more side bar, maximum. There are lots of side-stats who would increase game strategy: Tireness, sanity, overall mood, days without taking a bath/backrub etc. But please do keep in mind that too many "crippling" bars in a game make it more look like a Sim game, not an RPG.
It would certainly become more like a sim game. Keep in mind the opening post was talking about 'body management strategy', not game strategy. Not everyone is into 'body management strategy', it usually turns into doing set things at set moments. Eat 5 fruits a day, go to the gym 3 times a week, sleep at set times, do stretch exercizes at work... You can put it all in a game, but it are still chores.
Remember that no skill is required for resting, while already so much in Eschalon is tied to resting: hitpoints regeneration, weapon repair and finding ingredients for Alchemy.
Now there are suggestions for finding stones and managing a stamina bar through resting...
It's becoming a very, very cheap fix for all. Low on something? The solution is simple: just press the 'rest' button. But that's no strategy, folks.
Especially when pressing the 'rest' button would become the only
solution for a problem it's becoming really problematic.
Is that really what the suggestion here is about? A stamina bar that goes automatically down, simply because of being awake, and in order to get it up again you need to sleep, or perhaps buy a potion?
Sorry, I don't like being harsh, but the strategic depth I'm seeing here is zero.
I think I only know two games with a stamina bar. One of them is Dragon Age Origins. The bar there especially gets affected when you're using special weapon feats, so you can't use weapon feats continuously, but need a 'breather' inbetween. You can still fight normally when your stamina is down, but you don't have access to those stamina-expensive feats.
And the other game I know that uses it is... Eschalon Book II. It does the same thing to manage the use of feats. The stamina bar isn't visible, but it's still there.