I'm sure the devs already have plenty of ideas in this area but it wouldn't hurt to throw some more around. These are basically just random ideas that I haven't thought about a great deal, so feel free to tear them apart.

I like the thought of food being a more important part of the game. If you think about it, it really could be one of the most important aspects of the game. I think it should be an absolute necessity to eat regularly in PS to maintain/train your stats, it could also become an important social aspect of the game (wealthier characters eat better food, etc.).
System messages (those green messages??) should report when someone is eating something and comment on how tasty it looks to your character (Ylians may think apples taste great but Krans would hate them). Characters tastes in food could be randomly assigned during character creation and this could play a part in how certain foods affect you.
Most foods should minutely train stats (100 apples = 1 STR, 100 fish = 1 intelligence, etc.)
Combining stat training foods via recipes could increase the power of the training:
A = multiplier variable (could increase with difficulty level of recipe)
Apple Pie (skill level 5)
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5 apples (5 * 0.01STR * A = 0.25STR)
1 bag of sugar
1 pouch of water
2 bags of flour
An apple pie would sell for at least 1/4 of the cost of training strength and would therefore create a viable new trade for PS.
Please comment on these ideas or add your own.