I disagree
"1) Hit dice d8 (to show that they WORK for a living)
2) BAB to 2/3 (to shot that while they are not profresionals, the can fight... atleast at a reasonable level)
3) Make Fort a good save. (They do lots of constant physical labor. They need it.)
4) Weapon prof in 2 non-exotic, non simple weapons (Archery is VERY common for hunting, Maybe the towns people use Kama's for defence, or maybe some one figured out how to use grandpa's long sword)"
1) So a commoner is tougher than a rogue, as tough (and adept at dodging blows) as a monk, and equally hardy as a cleric. Hell no. Commoners by definition avoid danger. They dont WANT to adventure, they dont WANT their life to be threatened. When these things do happen, they largely freak out. They might make a wound worse than it is by not rolling with the correct way, or by being totally unprepared for what is coming.
The "commoner" who farms and fights bandits by day sounds more like the warrior, with some farming skills.
2) I dont think you understand BAB very well. Fighters live and die by their weapons, as do rangers, barbarians, and paladins. There are few if any sessions which these characters will not need to roll a d20 to hit at some point, which will use their BAB. It is their livelihood. Clerics, rogues, monks, and others with 2/3 BAB have many more skills and/or "powers" at their disposal. BAB is still very important, but they spend a considerable amount of time doing other things, or in the case of the monk, doing EVERYTHING. Clerics cast spells, rogues hide and go for sneak attacks, monks run around the battlefield helping where possible. A session may pass without them making an attack roll, but it is not the norm. Wizards and sorcerors are scholars and shamans. They conduct magic through themselves, not some divine power. A wizard or sorc rarely makes an attack roll at low levels, and if they do, its usually for a spell. Even at high levels, they are better suited to fling spells than swing swords, but they have picked up on basic tactics through observation and getting knocked around.
A commoner who hunts often may be a multi-classed commoner/warrior, a commoner who is particularly good at a trade may be a commoner/expert (or straight expert), a commoner who is utterly common, frightened of things in the dark, and working his butt off everyday of his life has little proficiency with said weapons. This doesnt mean they couldnt swing grandpa's sword around, they just wouldnt hit much (hence the -4 penalty). They could take Martial Weapon Proficiency - Longsword if they practiced a lot, but even then they wouldnt make for much of a combatant.
3) Do you think a farmer would be any better at resisting poison than someone who binds books or weaves baskets? If they are, they are an exceptional commoner and could take "Great Fortitude". Commoners largely live their lives trying to avoid anything in D&D that would CAUSE such a save. When people do make such saves, it is usually because of their inherent attributes (a commoner with a high dexterity may not fall to his death, he may even have "lightning reflexes", regardless he will do his best to avoid such occurences from happening again, or he will begin to take PC classes because the thrill stirred something inside of him).
4) A commoner is proficient with one simple weapon. Maybe a bully knows how to use a dagger, a sheep herder keeps a quarterstaff or a shortspear to fight off wolves, etc. A farmer might use a scythe to cut down wheat, but its a little different when you are using it to fight a person (hence the -4 non-proficient penalty). A farmer on the frontier may have warrior levels or may have devoted his feats to more PCish feats, like martial weapon proficiency or great fortitude.
DMG pg 38 "...commoners usually have no desire to live the wandering, dangerous life of an adventurer and possess none of the skills needed to undertake the challenges adventurers must face."
My emphasis is on "usually", in some cases they go on to become PCs. Other emphasis "none". Not one of the skills (BAB, HD, Weapon Proficiencies, or saving throws).
In closing, from the same page in DMG, "Player characters should not be commoners, since commoners make poor adventurers. Instead , the commoner class should be reserved for everyone who does not qualify for any other class."
The commoner is an important aspect of d&d, it represents the people that do the work adventurers rejected. Dont try and make them heroes against monsters, they are already heroes of another sort.
Technik