Hmm, I think you are mistaken. I am not sure which census you looked at, but Ragnarok has a very healthy population of around 12,000 characters. http://luckybancho.ldblog.jp/wsurvey...world=Ragnarok

Not even to mention, World means nearly nothing as they have implemented a system that everyone on the same data center can interact(you can even travel to the other servers through the aetheryte if you so choose). I think perhaps you are in the wrong state of mind as people do not "form parties" for level 37 content, you need to use the Duty Finder, which can be opened by default by pressing U. You then select the instance you want to do, then register for it. It will automatically place you with a group.

I do not play on the EU servers, but there may be some things that are impacting your play:
1. EU servers have unofficial nationality majorities. I do not know which is which but I know some mostly have German, some mostly have French, and some mostly have UK or otherwise. Based off of LuckyBancho, I believe Ragnarok is a 2/3 English and 1/3 French server.
2. You need to go into your Duty Finder settings(click the gear icon on the top of the Duty Finder menu) and select all 4 languages. This will improve your wait times immensely.
3. The time of day that you play impacts population greatly. if you are playing at 3AM, hardly anyone will be on. I don't know if you actually live in Europe, but if you play around 3-8PM Europe time or thereabouts, you will have more success.