Look, if NPCs sleep, eat, why player character should be like some ultimate killing machine being active all-time and without food??? That really drains role playing qualities of a game. I can't understand why they made it this way!
Note: NPCs and player character are intended to have lot of similarities (instead of Morrowind).
I'd suggest to make it this way:
--Sleep--
If "Sleep" indication is at very low then character would lose some of Intelligence, Willpower, Agility and Personality attributes (restored when sleep).
If "Sleep" is almost zero then screen could became blurred (like when suffering damage).
If "Sleep" indicating zero then character would be paralysed (if possible - laying like after a strong blow) for a few game hours until "Sleep" is at low again.
"Sleep" indicator becomes 0 (from max) in 36 game hours.
--Hunger--
If "Hunger" is at low - character would lose some of Strength, Intelligence, Willpower, Endurance and Personality (restored when "Hunger" is higher)
If "Hunger" is near zero then all the attributes would be damaged to 0.
If "Hunger" is at 0 then character would die.
If "Hunger" is max - character would lose some of Agility and Speed (restored when "Hunger" is lower).
There could be "Thirst" indicator as well (but with a bit different side effects than "Hunger")
"Hunger" becomes 0 (from max) in one game month or less and "Thirst" - in one game week or less.
For more realism there could be "Bladder" and "Hygiene" (from Sims

If when restoring "Bladder" there would be any NPCs around - their rating against player would gradualy drop.
If not restoring "Bladder" manualy - it would restore automaticaly, when being 0 but then Personality would be damaged to 0 and "Hygiene" would gradualy drop

"Hygiene" could be restored near the water.
All these 4 bars could be somewhere in journal menu (not to overload game screen)
And if it would take too long to make all this system then just make that - if "Hunger" 0 - player character die, if "Sleep" 0 - paralysed for some time. Later add more stuff

More requests:
As i'm such a realism fan i'd like to see options - "disable player-on-map indicator", "disable compass" and "disable quest info on map"
