I also have PCOS. As the others have said, you don't have to be overweight. I'm not. You're symptoms sound very similar to mine. My cycles were a similar length. My OB/GYN prescribed Metformin. That reduced my cycle to around 33 -45 days. So still irregular but much more manageable. The last two cycles were 35 days. I have just conceived my second on Metformin. My GP prescribed it this time. It sounds like the tests you have had done will probably be enough. If you need anything else, your OB can order it for you. If you are worried about insulin resistence, you could ask your GP for that test. Be warned though it takes about 2 hours so take a book or something. PCOS doesn't necessarily mean you are insulin resistant though. I'm not. When we were TTC DS, my OB said if Metformin didn't work, clomid would have been my next step. My dr also recommended the low-GI diet as this helps to regulate insulin.

HTH & good luck with your appointment in Sept.