Quality output check on my microdata 2 JSON-LD tool

Dear Gregg Kellogg,

For the last couple of days I have been busy with creating a tool to
convert webpages with microdata to JSON-LD. You can find this tool via this
url: https://www.seoprovider.nl/content/microdata2jsonld/
However, I haven't had the time to tidy it up the layout, but if you copy
paste the output to JSON-LD playground, I think it will look pretty neat.
(don't forget to copy paste the context to the context section of the
playground).

Anyway... my main question: "Is the output correct or do I miss something?"

Input:
https://www.seoprovider.nl/seo-diensten/snelheid-en-semantische-optimalisatie/<http://www.seoprovider.nl/seo-diensten/snelheid-en-semantische-optimalisatie/>
JSON-LD output:
https://www.seoprovider.nl/content/microdata2jsonld/?url=https://www.seoprovider.nl/seo-diensten/snelheid-en-semantische-optimalisatie/


For now all the @id's are the same as the input URL, but do you think I
have to be more specific on the @id's by providing the correct URI's that
targets a specific ID object?

-- 
Friendly regards,

Ka-Sing Chou
06 - 54 76 30 81
ka-sing@quantumspork.nl