Hello Slowtwitch, I'm quite happy to outline the nature of your problem on the basis of what is the most likely, and logical. In doing so I am aware of some limitations in the logistics of any solution I suggest. That being , there are some fundamental differences in the training and orientation between Aussie physios and US trained Physical Therapists. It does appear that US Pt's are more likely to offer exercise as the primary intervention, while Aussies are more likely to put hands on you to deal with the movement issues that are indicated by your list of signs/symptoms.
Your problems are all entirely explained by spinal protective behaviour. The end result of which has been to create an assortment of altered sensations and patterns of recruitment associated with nerve irritation. Note the predominant left sided aspect of the tightness and apparent hypertrophy.
Without going into the full detail of what spinal protective behaviour is , at a physiological level , it is normal , instinctive and potentially long term . Your spine will initiate a cascade of muscle tone increases to limit spinal movements when a threat is detected. The most common of which is sitting down.
The result of this protective behaviour is minor inflammatory events of joints and nerves. These nerves will then behave in a disorderly way , at the effect of focal irritations at or near the Wikipedia reference-linkfacet joints. leading to pain. muscle tightness and altered patterns of recruitment , often associated with weakness.
The problem in seeking help for this , is that these constructs are generally not well understood by doctors of medicine. It is my own observation that many PT's and physios are also not alert to spinal problems as cause, rather seeing aspects of altered muscle behaviour as primary , rather than a consequence of facet hypomobility.
So, what to do.
I suggest you stop looking for a pathological/medical answer or solution . Unfortunately returning to the doctors may well lead you to undergo improper attentions by those who ought to stand back. I speak here of surgeons. Remember , when you go to a used car yard , what do you get?, not hamburger. When you attend a surgeon , he or she will attempt to provide a surgical answer, that's what they DO.
Rather I suggests you make a list of local PT's ( assuming you are not fortunate enough to have an Aussie physio at hand ) and call them up. Ask specifically about their success and interest in manual treatments for spinal hypomobility. Avoid the ones who focus just on exercise, also those who will treat you for less than thirty minutes, also those who will not guarantee they will be with you and only you for the whole thirty minutes. Next eliminate those who have only been practicing for less than ten years. Also those who regularly use electrotherapies ( otherwise known as modalities ) as a primary treatment tool.
If there are any left on the list , make a booking, explain you want to have your spine considered and treated with manual therapies, in particular facet joint mobilisation.
Your problem begins with the Left > right L4 and L5. It is the protective behaviour around these joints that has given rise to neuralgic/neural events at you ankle/foot (feet). By restoring normal movements there , you will quickly find relief from the majority of the pain and altered behaviours of TFL, lateral thigh, peroneals and ankle. results will be within ten minutes , provided your chosen therapist is up to the task. Tyese results will be permanent , provided that normal unprotected spinal movement are restored. If not don't get trapped in an arrangement with no future. Be an assertive consumer. Keep looking till you find a manual therapist who leaves your legs ( and shoulders )alone and treats the cause of your spinal problems.
Best of luck