Bone Parent Constraint

I know that there is the child of constraint, but the problem is the bone will still inherit transforms from it's true parent. This poses a problem when you want to keep a specific bone hierarchy. It also doesn't support multiple parents.

There is also the armature constraint which is closer, but still inherits transformation from its parent. The armature constraint also doesn't allow you to change so it works on only one transform, ie. rotation, or location only.

A point, orient and parent constraint would be really useful. Without these constraints, simple things such as orienting the hand ik bone to the hand control become way more complicated and messy. The method I've seen online is to parent the hand to the control and then snap the hand back to the wrist with a copy location constraint. This feels like such a workaround because it's missing an orient constraint.