Indeed, the community agreement on 'entity' puts a lot of weight in the scale. In the end, evolving language is merely a tool to understand the experience for myself and to be able to communicate the experience so as to reach some kind of mutual understanding. That's the main reason I like to be active in the Lexicon. Developing new words and taking in definitions of others can function as a stepping stone to deeper experiences.
The names you have chosen for some entities might be arbitraty, but on the other hand, I think you did a pretty good job on some of the terms

for example, the flirty fairies, thats an entity one can easily recognize, just based on the combination of the two words.
I think it might be a good idea, instead of focussing on the diverse variety of entities on can encounter, to look for some overarching characteristics, and maybe even a matrix of characteristics. Maps can help to spot the uncharted and even to avoid certain domains, like the more negative entities. Thinking along the lines of general parameters like:
Location (local, hyperspace, beyond hyperspace)
Time (paleolithic, present, future, timeless)
Temperature (cold, neutral, warm) (like, some entities seem to have a specific warming or chilling 'feel' about them)
Light (intransparent, transparant, light emitting)
Regarding the essential nature, i'm not sure if there is a pattern that makes sense. On the other hand, the essential nature seems to be the most important of the parameters, but also the most difficult to classify coherent. For example, trying to apply esoteric categories like astrology or kabbalah makes some sense, but seems incomplete at some point or just not fit for hyperspace.
What you say about the negative entities: people seem to meet them anyway, and even though i agree with you that avoiding these entities & places is the best strategy, sometimes travelers get lost in the wrong neighbourhoods and some mapping or navigation how to know you are there (or slowly getting near the 'bad neighbourhoods') and avoid getting deeper might be helpfull to travelers if they happen to get there by accident. You must have developed some strategy during these 30+ years (impressive by the way

) to deal with these beings or at least the strategy to best avoid them?
Interesting how you explain your view on hyperspace. I recognize the architecture of the place you describe, the kaleidoscopic, folding rooms etc. I also recognize some of the other realms you describe. I always thought it might be nice to try to develop some sort op map, like i imagine the first explorers on the sea looking for new land did.