The Youtuber Artifexian has some good information on the topic, in which he explores star system and planetry building using equations (which I am currently compiling into spreadsheets for ease of use).
According to Artifexian's videos, The mass you gave is great (3.5 Earth Masses is the absolute maximum size I'd use to make a habitable world), and your moon should be less than the mass of your planet, but greater than 0.25 earth masses. This may turn your planet and moon into a binary planet system (like Pluto and Charon) so when calculating things such as orbit you may need to find the Baricentre of the two bodies first.