I haven't seen this yet so don't know if its been suggested or is planned.
There really needs to be a way to have a recon or ranger "class"if you will. Sure you could just hide and wait to attack players but that gets blan fast especially if you don't even have a way of really doing that.
some examples of ways to do this are:
this for would make surprise attacks/ambushes possible. they could also help with defense and be a tool for the smaller guy/tribe to use against the bigger enemy or vice versa to get those annoying solo griefers. can be used for hunting also.
EX1: Pit-fall traps, dig a hole use the skill to hide it and/or place spikes in it that cause damage when fell directly onto.
EX2: Spring trap, getting a tree limp tying it off with a couple, the more the more damage, spikes attached and when someone trips it they get impaled.
EX3: Bear traps, craft together some metal jaws and a spring for a huge damage dealing trap that you step on to trigger.
stealth could be used for a lot of things, hiding man made things out in the wilderness or concealing ones self. build a building and cover it in a camo tarp or do the same with containers out in a cool area you found. gather materials to be used as camo, mix and match to make the right kind for the area you happen to be in. this would be a big help for the loners out there or groups to small for tribes. Now i think the whole invisibility thing is just stupid, there should be real stealth/sneaking.
EX1: camo cloaks/tarps, these can be made via gathering the necessary materials and weaving them together to make varying sizes. maybe to cover a tent so it can't be spotted except up close, to lay over resources/bodies/containers.
EX2: Ghille suits or light camouflage, also collected from leaves/grass/dirt to help a player blend in with his environment and look like a bush/tree or snow...ect. Ghille suits of course would be much harder to accomplish and different environments would be easier than others to hide in. Would be used for hunting as well.
EX3: soft stepping/crawling, skill that improves with practice and better equipment like quite clothes and soft shoes, or none. would be useful at night, crawling up on a gatherer, sneaking through the woods up on a tribe, or trying to get through hostile territory.
Of course all this couldn't be added anytime soon but to have it being prepared for the future would be very nice. Also having things getter darker the father out you look would be nice for night.