I think having a single Arcade folder makes sense and keeps the structure simple, what might be useful could be adding a prefix in the name:
FBNeo - Mixed - 150 Uncommon Arcade Games (thingsiplay)
FBNeo - Mixed - Golden Age (thingsiplay)
FBNeo - Genre - Beat Em Up (hari82)
FBNeo - Company - Jaleco (hari82)
So they will “naturally” group up in the folder.
I would not want to add another layer of group to the filenames itself, because they start getting very long and are cut on my view of the GUI.
(And yes, I did not add any custom icons yet. I have my own idea what to do, but that’s for another time.) I use the RetroArch option to cutoff the first part of the filename, that is the display name of a playlist (wish there was a setting in the playlist to specify its display name). Adding the genre or group to it would make it too long to display.
But adding this genre and other group to the directory name is no problem, its just for the listing here. However, I’m concerned about breaking the connection of directory name and playlist filename after the first part “Arcade_hari82”.
Edit: Well after talking too much, I did the change anyway. Now the directory names include group information. We’ll see where it goes from here and if its a good idea. However it broke existing links in the replies to the files.
New playlist and a couple of icons : SNK pre neo geo, this is the reference used.
About the naming: my reasoning was that anyway (I think) people will rename the playlist files to their taste, for example in my case I have a different file naming (I use xmb).
I thought that the prefix were useful for the listing on git hub without creating new folders while maintaining readability. But if it break everything just leave it how it was 
It’s up. SNK is a good idea too, and I did not know there was so many!
For the naming, the directories including grouping is useful here. So I don’t mind that. And you are also right about people probably renaming the files as part of the import process; its no plug and play anyway. I was too focused on my own view. For now I am leaving it as it is (with the groups on directory names).
2 Playlists, I made a 2 playlists splitting my shoot em up list into Horizontal and Vertical monitor orientation: this means that in the horizontal category there are vertically scrolling shooters but with horizzontal (4/3) monitor orientation.
Nice. Especially because there are so many Shmups, this is a welcome addition. Do you think it would make more sense to put the orientation in the filename after “Shmups”, such as “Shmups VERT” or even write “VERT” out as “Vertical”? And should we rename Shoot em Ups list to Shmups, for consistency? Also I noticed that both lists added have 184 games, while the single Shoot em Up list have 177. Just some thoughts on things I noticed.
I’ll upload them shortly, after your response, in case something needs to be changed. BTW I’m working on a GUI app … that’s why I’m a bit quiet.
yeah probably Shmup Vertical / Shoot em up Vertical are both good!
Yeah I’m sill adding games sometimes and now my shmup list is indeed 184, but I think I added few other games in some categories, I was thinking to share the updated list altogether in a week or 2 so that the upload for you would be easier instead of updating them as I go.
