Aliens already changed everything - introduce a Queen, turning the aliens into mindless bugs. The first Alien was never made with Queens in mind because the xeno's actions don't make sense entirely if it was trying to make a Queen and not just more xenos. But Aliens is such a great movie that it doesn't matter so much.
If the Bros can make a really good movie - good characters, plot, script, style, music, etc.. Then the whole barfing thing and the designs won't matter so much.