more pictures of the desired chair here:
https://www.target.com/p/peoria-wood-arm-chair-project-62-153/-/A-50571247#lnk=sametab
also where you are seaming the pieces have you considered spicing with a butterfly or using a snug dovetail similar to the double jigsaw
https://makezine.com/2014/12/04/50-digital-wood-joints-poster/
I belive the cad files for each of the joints is available as well.
cad files et all found here:
http://www.flexiblestream.org/project/50-digital-wood-joints
no button but click text on right side of screen says download all woodjoints