I have not built a mini size plane, so take my advice with a grain of salt.
Rather than using one scale for the entire plane, I would feel free to change things, that is make them fit. I’d pick a scale to give you the wingspan you are aiming for. Use that scale for the wing cord, size of tail feathers and fuse length.
I would suggest making the fuse height and width fit the components you plan on using. I’d make the fuse width fit the mini power pod.