Folder Structure Confusion

I'm confused on how I want my folder structure set up.

1. While setting up Plex in OMV5 (using a video tutorial as my guide) I wanted to sub-folder the 4 folders (as shown in Files 01.jpg) into the Plex_NAS folder.
2. I thought by selecting the PleX device as shown in (Files02.jpg) that I was performing my intentions correctly
3. If I am restricted to the red outlined folders configuration of Files01 and Files02 does that mean the four folders are in turn likewise restricted to the total 170GiB of the PleX device?
4. Since I want greater storage capacity should I just resize the Plex device, delete it all together and just use /dev/sdb1 (WD4TBBlue1) for the four Plex folders, or just leave things as they are????
5. If I resize the Plex device I noticed that there was some sort of a raid warning. Is that of concern to me or do I just go ahead with a resize?
6. My thinking was: if I wanted Plex to be of server nature through my OMV5 environment that I would want my movies, recordings, photos, and config folder all nested in a device of it's own, but, maybe I'm looking at the issue/scenario incorrectly.

Kind of mumble jumbled confused here. Any help will be greatly appreciated in getting this set up in the best configuration and in turn functioning correctly.

Thanks Kai,

Could a moderator please delete this thread? It serves no purpose to me any longer because it travels down an unnecessary road. Thank you.