The Bone Amulet and the Tamed Skeletons.

Tamable Skeletons?

Yes, I think as mobs get harder and harder, I believe it would be great if we can enhance our defensive mobs. (The ones I know of that are "defensive" are snow golems iron golems, and wolves.)

How do we acquire a "Tamed Skeleton"?

In my mind, rebuilding a skeleton with bones might make way for an unlimited skeleton army, which is possibly overpowered should it not come with a limit to how many skeletons one player can tame. So the idea of having a block that consumes bones to spawn tamed skeletons might be overpowered, or may be tweaked to suit the game's feel.

The idea I think will work best is if the player has to wear a Bone Amulet. The amulet will take the slot of the chestplate, similiar to the Elytra, in exchange for the best armor slot in the game, you get to carry along side some skeletons by your side.

But, how many skeletons should you be allowed to have?
Personally, I think this should depend on what you craft the Bone Amulet with.

1. Iron Ingot    2. Bone Block                     3. Iron Ingot  
4. Bone Block 5. Insert rare material here 6. Bone Block
7.                     8. Bone Block                    9. 

The Rare Material
Tier 1. Gold Ingot - 1 Skeleton
Tier 2. Emeralds - 2 Skeletons
Tier 3. Diamonds - 3 Skeletons
Tier 4. ??? - 4 Skeletons (I am not that experienced with the game to think of a rare material that isn't too rare, or maybe diamonds should be the cap)

Okay, great, but how do we ACQUIRE skeletons to follow you?
By equipping the Bone Amulet, and then going out into the night to recruit the few nearest skeletons.
But maybe also give a visible cue as to know which skeletons are on your side, like maybe giving their eyes a special glow. To differentiate your skeletons and enemy skeletons.

Endurance?

I think the endurance of the Bone Amulet should be equal to the Iron Chestplate. Even though it does not provide any actual immediate protection, it still carries your skeleton crew around. So taking damage to the chest will damage the Bone Amulet similiarly to the chestplates.

Uses?

Skeletons will immediately attack hostile mobs within a visible range of 10 blocks, or pursue mobs you have attacked yourself.

YOU CAN TAME WITHER SKELETONS! It kind of defeats the purpose for me as this is for ranged defenses but if you want to bring in the big withering boys I see no reason why not. (Or, we can make a sub note for the Bone Amulet, like using a wither skull instead of diamonds)

Skeletons can equip armor YOU as the player provide for them. By holding it in your hand and interacting with the skeleton. You can also swap out their current weapons and armor this way. Skeletons without helmets cannot follow you out into daylight, and will hide in the shadows until nightfall returns. To change that, just provide them a piece of headwear

Unequipping the Bone Amulet will make the skeletons revert to their original state after a few seconds. They will still be wearing your armor though, so I suggest removing them before doing so.
On the other hand, you can hang your Bone Amulet on an armor stand or frame it, to get your skeletons to defend the area. (i.e Placing your Bone Amulet in the heart of a village will make your skeletons attack hostile mobs within the area, but once your skeletons die, they cannot be replaced unless the player reequips the amulet and recruits new skeletons.)

 Other spooky and noteworthy features I think should be addressed:

• You can heal your fellow skeletons with Bone Meal and Milk. Bone Meal should restore about 25% of their health while Milk should restore 50% (I am considering the versatility of milk here, but this can all be changed)
• Although they cannot drown, bringing the Bone Amulet with you into water might be pointless as the Bow and Arrow have near to no use underwater.
• You can tame Spider Jockeys if there is space in your skeleton crew and the next closest skeleton is a Spider Jockey.
• Peaceful Pact: Your skeletons will not harm your pet wolf, nor should your wolf harm it.
• Adding the Bone Amulet with the features above will allow potential for wild biome spawns, like Bone Temples where the skeletons are all guarding the amulet and in the heart of the temple lies an Amulet the player can acquire. (Maybe this is where we can get the Bone Amulet Tier 4 in vanilla playthroughs?)
• Strays should also be tamable.
• Spooky Halloween Skeletons with pumpkins on their heads can also be tamed.

Author's thoughts and overview:
To summarize, this will be a great way to recruit one of Minecraft's most prominent ranged fighters to defend us, our villages, and our mobs. Although they may not be as tanky and capable as the Iron Golem, but at least they have range. If the idea of taming other skeletons such as the Wither Skeleton, the Stray, or the insanely overpowered Halloween Pumpking Skeleton, is too good for the Bone Amulet, then I am more than pleased to agree removing its ability to tame other skeletons than our basic classic Bow and Arrow Skeletons. Leave your thoughts and ideas below for me to hear out! I would be glad to be able to hear what the community has to think about my first idea for Minecraft.                                    - Jaydonius