I am planning to add some devices/receptacles to a 20amp circuit in my house. The following image shows the original circuit and my proposed additions. I'm specifically concerned about my plan for wiring outlets after the GFCI tester (see items 12 thru 17 in the image). Three outlets will be wired in parallel from a junction box directly after the GFCI tester, with two additional outlets wired in series off of one of those paralleled outlets. Are there any problems with this plan? Any input or confirmation is much appreciated. Thanks!
Electrical cable/conduit routing must be tree topology
You can also wire things in a "vine" topology, like 12-15-16-17 - after all, a vine is a type of tree.
You can also wire in a star topology (like 12-9-15-14-13). That counts as tree topology also. (but with many connections, box fill rules must be followed just like anywhere else).
You can freely mix them all.
Here's the acid test: In your graphics editor, take your cabling diagram (remove the non-cablng elements like gray walls). Now, grab the paint can tool, and pour purple color anywhere on the diagram. Does it fill the whole diagram? Then you have tree topology. Yours appears to pass.