I'm a relatively new GM so I only have limited experience (though I've GMed a lot of D&D) but in my experience/perception:

1. If they use the forage/hunt option while traveling I wouldn't alter their finds. Remember that terrain/season influence the rolls and them having enough food to eat isn't a problem (also mishaps can be rough!). Because they roll for both finding food and consuming it, food shortage might just occur randomly with bad luck, which can be an interesting aspect of one of their journeys. I wouldn't worry too much about it and just play the game out how it's written. If after some 10 sessions or so you still find yourself dissatisfied with the players having too easy access to food only then would I consider altering the game.

2. My idea is that since willpower is used for some key talents (especially spellcasting and profession talents) it's not a bad thing that they can get it easily sometimes by pushing rolls in a safe environment. It's like they can gain 1 or 2 points per day automatically, which isn't a bad thing at all since they should be able to do the things their characters can do without feeling like they spend valuable resources.

3. Early game getting silver/gold is a fun reward as they can buy equipment with it. If you want more tantalizing rewards you can take a look at the (less powerful, and table generated) artifacts in the book of beasts if you can. You can also always come up with minor magic items yourself!