I think the option to fletch your stone and bone arrows with chicken feathers would be a useful addition. It could increase the IEMM of the arrows, or decrease the aiming time of the bow, I'm not too sure which would be better.
Anybody who's ever tried firing an unfletched arrow at any sort of distance with anything resembling accuracy would know that it's very difficult- an arrow with fletching makes a world of difference. To be reasonable as far as materials go, so that you don't have to kill a chicken just to end up with one fletched arrow, I think a feather and string of any type could suffice for one.
Seeing as chicken feathers and string are easily obtainable, this addition to the game could give relatively new players access to the greater hunting prowess offered by bows, without need for too high of a marksmanship score. It could help give aspiring archers a chance to take down bigger prey earlier and easier, along with adding an extra tier to the archery combat system.