one piece i highly recommend is running your torrent solution in a container with the network set to a gluetun container. no fuss, no muss, vpn'd torrenting.
for the nas piece, im a big fan of the nas device being single purpose. its life should only exist in fileserving. i have several redundant nas devices and then a big ol app server.
my goal is the ron popeil method of 'set it and forget it'