Wow,

If only all case studies were that detailed.

You have already self problem solved much already. Surely you deserve a warranted response.

Whether you have any real underlying issues, or merely postural and muscular balance issues that are related to the types of activities you wish to undergo is difficult to tell without seeing in person. One could easily have postural issues, and not necessarily any pain. The reason being your body adapts to the position it is in. Pain is the result of overload of soft tissues or impingement/irritation of nervous tissues or structures that surround the area of discomfort.

It appears that you are suffering from over use of your limbs post- trauma and long term muscular problems created from wearing splints, suffering un treated injuries, muscle wasting and much more. Surely a case like this requires great deal of examination.

While the make shift self treatment you have created is great, works for you wonderfully, ultimately it is very much necessary to improve the dynamics of the joint (knee) so that it matches and meets the demands of the activities that you wish to perform.