Initial feedback

Looks good.

The reason that I wanted the Ronaldo example or the Donald Trump one was that I wanted an example where we needed a reified entity to make it work. You say you need reification but none of the examples use it. (I think this is one of the problem with large scale KGs; that they try to avoid reification, often losing information. Perhaps include the dates that Ronaldo was captain of Portugal, or played for each club he played for. (See https://www.wikidata.org/wiki/Q11571)

Club-position is a weird property, as what if someone played different positions for different clubs?

On https://www.wikidata.org/wiki/Q11571 it is "member of sports team" (https://www.wikidata.org/wiki/Property:P54) that requires reification. I am not sure how it is actually represented in wikidata. (Think about what it is that ends on 1 July 2009.)

Thanks, If I want to include information about the time period then I think I will need reification.