@TFG I have something like a month-long outage in the lab in my home country because I didn't bother with Windows firewall and an anti-virus. So yeah, if you aren't ready to redo your whole set-up and check for exploitation impact, I'd say that having an antivirus and a firewall on a windows host itself is a good idea.
I've tooted a while ago that Windows machines are still more or less attack vectors and it was stupid of me to think otherwise.