IMHO, running OS3.9 without a graphics card is fairly pointless... You'd be better off running 3.1 and getting updates to "make it look pretty" plus necessary filesystem driver updates, etc, from Aminet.
never had a problem - in fact some of those pretties were starting to be integrated better into os3.9 with stability being improved.
My OS3.9 system for years was A1200 030@25MHz with 8MB Fast RAM, a 2 port IDE dongle with a CD ROM.
I used to surf, and email from it - I was even able to do those two things concurrently, and no graphics card !
of course its NICE to have graphics cards, and its more convenient, but pointless ? no...