I think you will do fine with the 1 shot per week of bicillin.
It is good that you are on biaxin now. In my opionion, it is one of the most effective oral meds in the lyme world. It affects many different creatures, some more than others.
With the addition of plaquenil, you are covering even more. The leg pain you are experiencing is most likely a herx. Some often see this in the leg that had "the restless leg feeling" before treatment started. You will sometimes get this pain more in one leg versus the other. It is very hard to say what is affecting what with your combination. And any of the 3 B's could cause the leg pain, whether it be borrelia, babesia or bartonella. Some theorize that plaquenil makes the biaxin penetrate better. That is just a claim as far as i'm concerned. I won't go further into it, nor do i embrace the idea. Nothing is proven with the plaquenil ph lower effect idea.
But plaquenil is a mild/medium antimalarial and has some decent anti-inflammatory properties. Biaxin also has some slight antimalarial properties. Biaxin also has an effect on lyme and most likely bartonella.
Biaxin by itself isn't the most exciting thing. You can combine it with many other different drugs and get all sorts of different results. It was always the main tool in my past treatment for bart and lyme.
Some of my favorite biaxin combinations for lyme and bart was:
Biaxin/Doxycycline
Biaxin/Minocycline
Biaxin/Rifampin
Biaxin/Bactrim
or Biaxin/Amoxicillin
Also, i'm not a huge fan of the sporanox your dr has you on. That stuff is a little creepy if you ask me. It is getting up there in toxicity. Not as nasty as lamisil(the nastiest of all antifunguls) but getting close. I think you could do just fine with a small dose of Diflucan plus oil of oregano and olive leaf extract. Much safer in my opinion. Your dr must have something against diflucan.
Well good luck. Don't let go of the biaxin. It is good stuff.