Snoke, I have to say, is where the movie proverbially ‘shit the bed’. It’s just not good enough fx to pass as authentic, and really shows up as a CG construct.
There are more issues with Snoke’s hologram. According to the script, in the first scene with Snoke the audience is supposed to be led into thinking that Snoke is a real person and not a hologram until the transmission ends. This means that the fidelity of the hologram has been made higher than any hologram in the OT or PT, in order to pull off this trick. Personally, I don’t see the point of that at all.
Also, the hologram room has windows with sunlight shining behind Snoke, and that light should reasonably make the holo-projection suffer, but it doesn’t and that just looks weird.
I think best would be to first reduce the shots of Snoke to a minimum – making him more of a mystery, as the Emperor in ESB.
Second, if possible, lower the fidelity of the hologram – which I think would mask the low quality of the CGI and make the hologram look more like a hologram in Star Wars should look. Mask off Snoke from the background, lower the resolution of the holo by dividing into artificial scanlines, add noise and possibly interference, give it a blue tint and add that onto a new background that does not have a light shining directly into the camera.