It looks really good. I have a sit-stand electrical desk. Probably I can create something like this for using on top of it. The white pained legs, is that also wood? What method did you use to attach them to Top?

  Unless there is some issue ( Health wise ) with Tree, why to even cutoff 500 years old tree, just to make a big table for 60 people ? 
     Most of us die between the age of 60 to 80, It successfully lived 500 years. They could've left that tree as it is for future generations to see and experience it in awe.