I still have a hard lump of scar tissue and a puffy nipple. Being 8 weeks post, is this close to as good as it gets? (photo)

You are way too early in your recovery to see your final results, it may be several more months of healing. Scar tissue behind the nipple does form for many gynecomastia patients after about 4 to 8 weeks. It may eventually resolve on its own, or your surgeon might inject steroids to help break it up. Good luck. 

I'm sure this is very frustrating.  You probably feel like 8 weeks is a long time post-op.  Many men do have what seems to be a full recovery almost immediately. What you are experiencing is likely part of the healing process and may resolve over time without need for additional intervention. Do share your concerns with your plastic surgeon. he or she wants you to have a great result and recovery. Your plastic surgeon will want to know about your concerns and put your mind at ease, or discuss options for additional intervention. 

Unfortunately I see this all the time.  Your surgeon did not adequately prepare you for the postoperative course.  Scar tissue, after surgery, peaks about 6-8 weeks after surgery.  So you are in the scarring period. After this period comes the scar remodeling period. This takes about eight months to a year.  During this period the scar tissue will soften and the scar will settle down.  So if you're still dissatisfied in a year then talk to your PS.