Don't know if you've had an OLED before, but they all do the off-axis colour shift to some degree - it's a characteristic of the screen and looks very different to the off-axis appearance of a LCD. re: the yellow, remember (a) it has True Tone and (b) whatever you're comparing it to screen-wise might be too blue. FWIW I noticed both of these to some degree on my X, after about 24h didn't think anything of it and it's not bothered me to this day. If you really can't cope with it that's what the 14-day return window is for. 😉