Hello Naviaras
What you have described is on my list of systems to build, the only real difference is the main tube size. I plan to use a 8 or 12 inch PVC tube. You should be get them at most any pluming supply house (not Nome Depot and Lowe's), dedicated pluming supply places. Although I may use the 6 inch tube for smaller plants like herbs. But use what makes sense to you, and for what you plan to grow. I guess the main thing I might add is make sure your support will be sturdy, easy to build with available materials, and of coarse functional. You don't want it to become top heavy, especially as the plants get bigger. And if it's going to be outside you don't want a wind gust to knock it over.
Just for the heck of it, I thought I would add some images that I already had on my designs. I have drawn them up in various configurations. Mostly in a single tube design with the reservoir at the bottom, and in a multiple tube design with a single reservoir. Then with a few different options for support. And although the single 1/2 inch tube down the center was also my plan, I drew up another option for a couple of reasons. The second option would not need a bottom support to hold a vertical mister tube centered, and because water will drip down through the tube, it will take less mister heads to get the same basic coverage. That might be important depending on the water pressure the
pump can put out, especially if using a multiple tube design.
Jet me know if you have any questions, I know witch pictures go to what design, and that may not be obvious to other people, also there not in any particular order. .