I feel your pain! I’ve had poor results exporting 1280 x 720 29.97 MP4 H.264 with a bit rate under 5000kbps. Blocking, artifacts, etc…
I’m sure there is a way to optimize and get good results at lower bit rates and am looking into “episode” from Telestream. It looks like it may be a good solution if only I knew how to orchestrate all the variables. Does anyone know a good primer for optimizing H.264 low bit rate encoding?