I always get so pumped when Terminator movies come out on a new medium. From watching it on TV with my dad, it was awesome, then we got it on video, then DVD, and I was super pumped when the blu rays came out, but the Blurays really highlighted how bad the effects (especially in the first one) were.
I hate to imagine how crap the effects will look on a 65" OLED 4K TV.
I get that it's turning 40, and it's a good movie, but even T2 on 4K barely passes, and that's only because it's a timeless masterpiece that I'm more forgiving of the effects because everything else rocks. T1 doesn't have that luxury.
Either way I'm sure it'll piss a lot of people off! If there's too much grain removal wax statues, colour correction, and enhanced effects, the people who've been watching it for all 40 years will hate it, and if it doesn't have all the fixes everyone else will hate it.
A cleanup will just make it look good, and if the whole movie is wax, the bathroom face removal scene will look better in comparison. Unless they want to fix that scene with modern computer graphics. Also, fix the models in the opening while they're there.
Don't have to remove or change entirely, just a little touch up with more modern effects.