Hello,
I use Ubuntu 16.04 on a Mac mini and on a HP EliteBook, and the version of Insync 1.4.3.
When I started to apply to put my e-mail folder to my home folder, then there wasn’t a following setting, i.e., selective sync. Insync ends up syncying everything - all folders and all subfolders… I have already synced only few folders, but Insync has kept syncing everything.
It is not because I chose 1.4.3, but your download page downloads 1.4.3 instead of stable 1.3.
Different of macOS, on macOS, Insync has a selective sync settings and lets me select only few folders.