No further work yet on the case. The holidays have been slowing me down. But I have a new job and more income coming my way. Also I plan to soon buy a HD-PLEX Silicon riser cable with some of my Christmas money.
For now, the measurements of the case are 98% final so I've made some better mockups on two layouts I'd like to use for the case. They are to scale- 2 pixels = 1mm.
The first one is with my current set up of parts, with the mini GTX 1050.

This layout supports up to four 2.5" hard drives stacked on the bottom panel of the case and attached to the front. To accommodate the hard drives, the graphics card MUST not be longer than 5.8" which is a common size for the smallest mini GTX 1050 and 1050 Ti cards. Now that this is about one inch shorter than a mini ITX motherboard. The HD-PLEX DC 160W unit is at the bottom edge of the case. Power cables can run in the space beneath the graphics card, to connect to the AC-DC unit at the top right.
Now for the second layout, a more daring proposal, the "YOLO power build" using a GTX 1060 6GB and with the same 160W power setup.

With this setup, you'd only have room for one 2.5" hard drive, but having a GTX 1060 powering a 1080p monitor at 144hz can be worth it. The reason I'm speculating this setup is, although this graphics card is rated to run at 120W, power consumption is actually lower at 1080p gaming- closer to 90W. So as long as I use a 1080p monitor and a 35W CPU, I could theoretically stay below 160W power and rarely hitting the peak load of 200W.
If it turns out to work it would be a great power-sipping machine that can rip through games at 1080p.