Comment by LinuxBender

Might one mitigating possibility be to use a VPN that uses padded and rate limited packets, so that it is always sending and receiving user_defined bit rate and your real traffic would be traffic shaped to take priority but not exceed the padded streams? Maybe this assumes one is running their own tor daemon on a server somewhere and the vpn terminates on that node. I assume this could be done with tc sch_htb class shaping or perhaps sch_cake and tagging packets with iptables mangle rules and two never-ending bi-directional rsync streams reading /dev/urandom or big random files.

e.g.

    Port 873 (native rsync) bulk traffic, low priority
    Port 3128 (squid mitm ssl-bump proxy) high priority