Overall game time was 230hours (half of which was not even going for crowns or trophies).
All my gold crowns for non elder dragons were from the event quests. - very easy to spam the events until you get all the small and large crowns.
Elder dragon crowns I just joined other players investigations until I was lucky. The most kills for an elder dragon and the one that took me about 10 hours to get was the small crown for kushala. - 74 killed before I got the small crown.
Loved every second of this and ready for iceborne now
If anyone wants help with crown/investigation farming I’ll be happy to help.