The GMP is not intended to be objective. It never was. In the beginning it was meant to show people the way to aesthetic or otherwise engaging locations, places that by the founders of the GMP were found to be out of the ordinary and to make others aware of. I think that was even before EDSM and other contemporary 3rd party tools with a map display capacity were even available. Of course, the more people went out there exploring, the more those out of the ordinary places became ... more common. Nowadays, you possibly have tens of thousands of people going out there finding new stuff all along and sometimes FDev even introduce stuff where you have to decide on how to handle them as new possible POI categories.
All this is done on a subjective basis. We are no algorithms running star catalogues or the SIMBAD base through a whatnot and put them onto a map. If you want that, you won't get it in the GMP. It's that simple. However, there is no issue with some other folks using, say, the Henry Draper cataloge and create a map of their own. Lots of people have done so before and are helped by said 3rd party tools in ways that were not available in let's say 2015 or '16. A map with all planetary nebulae sounds like a good idea (although it may get a bit crowded in the Core), as is a map of neutron highways, Wolf-Rayets or "The Badlands". You just can't do it all on one map.
Just because things are not done in a way some people like them to be, doesn't mean it's rubbish. As you have your valid reasons to do things otherwise you will please acknowledge we do things in the GMP the way it's meant for five years now. Both are legit ways to maintain a community project.
The GMP will likely always use a system of POI types sorted by 'visit worthiness" and it will be judged upon by the project admins with a number of criteria and some manoevering room for good stories, good footage, exotic location or otherwise "soft" factors in mind.
To all those who have happily contributed over the years: Thanks for your dedication and efforts. See you in the black!