Before going any further, I'd like to mention that my caste system is based on the far east, with heavy influence from India and Japan.
I would suggest the benefit of the Peasant Caste to be that everyone doesn't hate you. I imagine many peasants having a view of the world like 'All these nobles do is tax our crops and sit in their castles drinking wine, all these warriors do is recruit young men to go to their deaths in wars they don't understand, but you, fellow peasant, are all right!'
That's not a bad idea, but I think anyone who belongs to a certain caste would get a "Charisma" bonus with others of his own caste. So it's kinda a given. Also, it not like everyone in a certain caste would think or act like everyone else in his caste. There be humble nobles that looks after the people under him, and proud arrogant peasants.
For a peasant to do well he should be better than normal at whatever he wanted to do, so I imagine something like an extra trained skill, but not everything should be available. The list provided by @
Arctic Wolf is a good start, but I would also maybe add Athletics and Endurance. As an additional fluffy/thinking outside the box bonus you could also add a small bonus for the purposes of ability check rolls, something to show that they are hard working or know how to apply themselves (for example +1 to all strength checks).
In my setting peasants are the untrained average Joe. The Merchant/Working caste already get a bonus skill (A craft, profession, or preform skill of their choice). Also, I think a +X to X skill(s) would be both bland, and kinda cookie cutter. I don't want it to to seem like all peasants are good at gathering information, finding food, or even worse that they are all thieves (I know, thievery doesn't necessarily mean pick pocketing, but it one of it most common uses)! Lastly, I tend to lean toward extra class skills or a bonus to class skills as background benefits.
The only skill bonus I'll keep in consideration will be Endurence or Streetwise.
And I'd also give a bonus to Fortitude. It's not that being a peasant makes you hardier, but that only those with greater resilience can survive the hardships of a peasant's life.
A bonus to a defense? Hmmm.... not bad. I could see how peasant's life would lean toward needing better than average resistance. Maybe a few more hit points would also work?
... peasants know how stay invisible or at least not be noticed...
Lol, I thought of this to. Something along the lines of 'When in a town or village, you look so much like everyone else that you blend into the crowd. You gain concealment when not drawing attention to yourself (Combat, yelling, juggling, and ect.).'
If you want to give them something usable in combat too, you might consider a feat improving survivability, like an initiative boost, Toughness, increased healing surge value, or the one that gives you temp hp when you use a surge.
Which skill training and which combat benefit they get would depend on background - a huntsman might get Nature and Toughness, while a thug might get Thievery and Quick Draw.
Most of the feats you mentioned are too reliant on background, so if anything I'd only give them away as uber background benefits for uber good background stories.
Serfs could have weapon proficiencies too (remember the flail was mostly an agricultural tool, as were many polearms). Weapons training was also enforced - for example, there's evidence British serfs were obliged to practice the longbow every Sunday.
My Warrior caste already has this covered. Don't want my peasants to be stepping on the Warrior's territory, or my peasants to seem like weaker Warriors. Also, because of the Japaneses influence on the setting, only Warriors are aloud to openly bear weapons in public.
All said, I guess the one thing that really sets peasants apart is the fact they're predominantly farmers - so of all the peoples in the medieval world, they're the most in tune with nature. You toyed with giving them a magical benefit, and in a high fantasy setting, I'd be inclined to stick with that. Something primal, e.g. daily access to the Shaman's Speak with Spirits. I imagine the Feywild touches those who tend the land, so your average farmer is constantly wary of spriggans souring his milk, or pixies putting tintacks in his boots.
Another thing I forgot to mention is that your caste also filters what classes (Or power sources) you can play. Peasants can pick from Arcane (In thier case flavored to be "Elemental"), Martial, Primal, Shadow, or a Monk. Out of all the Castes, peasants have the most caster class available to them ("Elemental" and Primal are archaic traditions no longer taught or believed in by the upper classes.) So they definitely would have more magical connection than other castes. The problem is however is that I already have a caste that gets a magical benefit (The Untouchables, whose labor forces them to come in contact with unclean things that curse them with magical like abilities. The other problem is that, if all peasants have such a innate connection to magical powers or beings, then why don't they overthrow the current ruling caste? Simply, it makes peasants seem too powerful.
Could be possible, but it need to be balanced somehow.
Keep in mind that these are backgrounds for characters who are, or will become, heroes. So the question is not "what advantages would a typical peasant have?" It is "what advantage would a very non-typical peasant have, the 1 in 1000 who will not slave away on the farm 16 hours a day from age 8 until he dies of malnutrition at 35, but instead breaks free of his background in search of something greater?"
Well, that depends if the PC plays himself as a above average PC. What if a PC decides he wants his character to be the loyal slave of the Noble PC's character?
A bonus to Endurance, or to Will (maybe to all saving throws, since it's a lucky peasant indeed who finds his or her way out of peasantry), would be my choice.
Again, interesting.
Ideas I like so far:
* A bonus to a Defense (Will or Fort), bonus HP, or +2 to Endurance.
* Gaining Social Concealment.
* A minor magical fluff.
* And one I came up with myself, A Hometown advantage. Basically, peasants are more loyal to their own then any other caste. While in their hometown they gain some kind of advantage (Not sure yet) and can send letters to their hometown elder to ask for support (And be more likely to get it then any other caste).
Although that's an important legal distinction. Serfs are not slaves - they may not be sold or have their family broken up. On the other hand they are legally tied to the land they are on and may not leave it. And when the land changes hands they change masters.
