Interesting!!! I did self-study also and work with other engineers and architects, thinking that I am a manager but I'm not! hahaha... Maybe my knowledge or experience is better than them?

What are you going to use to cover this huge sphere? For the steel post in the middle, what is the radius or Diameter that you are going to use? I suggest using 50 Diameter is enough to hold or to support the entire area but in Octagon shape! Better to make 22 Feet or 6.7 meters Height including everything. Take a look at what I did...

This is just an estimated example... Instead of or using a round shape, use HEXAGON.