I think it should affect it fairly substantially. It should effect it more negatively if it has bad graphics then good graphics would affect it positively though.
Like a game with awesome gameplay that would otherwise get a 10/10 should only get about an 8-8.5 if it has horrible graphics.
If a game is average like a 7 gameplay wise but has amazing graphics it should only be bumped up to a 7.5 or 8 at the very most.







