sndwv: Thanks; I'll take a look at these! I want to stay as close to original as possible (just make it work) but I see that some of these ports do just that. Was put off the whole port concept a bit remembering videos of 'enhanced' Doom ports etc. that looked really garish to me, adding all sorts of lighting and filtering effects that looked out of place, but that doesn't appear to be the case with these (though at a glance it seems Quakespasm will need some configuring to turn features off).
I would recommend the following console commands
gl_texturemode GL_NEAREST_MIPMAP_LINEAR
and
r_particles 2
but that is a matter of taste. The defaults should be GL_LINEAR_MIPMAP_LINEAR and 1 respectively.
I disable auto aim (sv_aim 1) and play with a crosshair (crosshair 1), but that's obviously not vanilla.