Quality review requested on JSON-LD output based on existing webpage.

Dear JSON-LD Community,

I have been studying JSON-LD for a while and I just did an attempt to
create JSON-LD based on an existing webpage. However, I have no idea if the
output is correct. I really hope you guys can help me out a bit:

JSON-LD: https://www.seoprovider.nl/seo-pakketten/mkb-geavanceerd.json
Based on: https://www.seoprovider.nl/seo-pakketten/mkb-geavanceerd<https://www.seoprovider.nl/seo-pakketten/mkb-geavanceerd.json>
/

Anyway... a contextless json-ld, which contains every detailed information
is also correct, right? If someone has a better idea on how I can improve
this, please let me know.

Big thanks in advance.

-- 
Friendly regards,

Ka-Sing Chou
+31 6 - 54 76 30 81
ka-sing@quantumspork.nl