Alright comic wise, I would say that venom started off stronger than spidey and spidey never displayed an increase in strength while he wore the venom symbiote or any other black suit.
in the tas cartoon, i would also say that venom was stronger than spidey since spidey mentioned this and was easily dominated by venom in battle (in normal clothes). In comparing their black costumes to one another i would still say venom was stronger because of a stronger bond between them.
based on this stronger bond analogy and the fact that we get the impression that venom kept the costume on continually and didn't keep putting it on or off and driven by the suit's rejection (if it was sentient), i would say that venom was stronger as well, even though there is no true evidence to support this claim. Saying this though in the hollywood tradition of having doppelgangers i could give argument to show venom was probably around the same strength as parker in the suit.
I don't think the suit's reaction to strength enhancements are based on the superhuman aspect rather the strength of someone. I think it is a size multiplier and doesn't take into account pre-existing strength tendancies (but takes into account strength of the bond and the longevity of the host wearing it).
so a smaller build superhero would not see that much of a increase in strength than a laregely built normal person.
so give it to giant man and we're in serious trouble.
t:
