You may also want to do a quick check for trigger points in the Pectineus, Vastus medialis, Gracilis, Adductor magnus, and Sartorius (you've already had that worked on), as they all have referral patterns in various parts of that area. Could be your previous muscle imbalance issues left you with lingering trigger point issues. If so, very easy to release. See TriggerPoints.net for more info at Hip, Thigh, and Knee Pain A great book for the layperson on the topic is Clair Davies Trigger Point Therapy Workbook.

And just checking for red flags: are you having any numbness in your pelvic floor area? Any trouble with bowel and bladder?

Questions about your bike, are you using "clipless" pedals? If so, can you get refitted to take into account the angle your foot is held in? Sometimes an adjustment can make all the difference. What about your seat? Sounds like you may be getting some compression issues going on in the sit bone area. Checking with your bike shop on seat options may also help in this area.