Well IMHO that looks a mess. I s’pose if the user could draw each icon, position it and name it then in that users eye there would be some semblance of order. Sorry but I don’t see any order in that pic, but who am I to judge? I only know how blender displays and orders its “things”.
In the future you may be able to make your own icons but in the outliner each bone has an icon as well as the name of that bone which you can select with LMB or RMB-SELECT with the armature in pose mode. As I said theres no way to change those icons though. Click the dropdown arrow nextto pose or hit NUMPAD-+ to display the tree and all bones are arranged in their skeletal order, more obvious than the pic you showed I think. To clean up the outliner display you can change the ALL SCENES to SELECTED or ACTIVE or whatever you choose.
For the display I’m not sure why you insist on wire drawtype? Using octahedron or stick display as either shaded or solid the bones are all sufficiently and coherently displayed. You can also use the layer manager under display options to isolate parts of the rig on one layer while hiding others on invisible layers to keep your workspace clean.
Sorry if that’s not what you want but thats the way blender works.