What percentage of further hair growth can one expect after the 6-month mark? (Photos)

Generally speaking, you're around the halfway mark (50%) and will continue to see further results. You can expect to see full results once you've reached your 1 year post-op. For optimal results - follow your doctors medical management recommendations. The link below references some of my hair maintenance recommendations for maximum density.

It may take six to twelve months to appreciate the results of a hair transplant surgery.  If you are concerned it is best to contact your doctor.  Some may not see any results at 6 months.

6 months post operation gives you the 40-50% of your total result. You need to wait for a year in order to see the complete look

At 6 months you will be at only about 50% growth, at 12 months you will be at roughly 90% growth. Remain patient and continue to follow your doctors post op care instructions.

My standard answer is that 80% of the hair will grow to styling length in 8 months and the rest in a year

The most noticeable hair growth will start to happen between 6-9 months. It will still take a full year for all hair to grow. By 9 months you should be seeing about 80-85% hair growth.