Is it better to have a slightly off color from the normal pure white?

It is purely a matter of personal preference. In the right setting, white walls can be beautiful. It all depends on the room, natural light, lighting in the room. I, personally have not found them to be glaring at all - this goes back to the lighting issue and also what type of finish on the paint you choose. I am not fond of eggshell finish or any "flat" finishes, but that's my taste, not yours. I favor "blue" whites over "brown" or "yellow" whites. Just know what you see in the paint store will look completely different in your home. Get paint swatches and when you narrow it down, get paint samples and put them up.

I use,color on walls and ceilings with off white trim. White wall seem to sterile for me and I think look cheap. But only an opinion.

Thanks Naomie, For your helpful ideas, I see decor pictures on the net with white walls & it is hard to tell whether the walls are white or not , as you say try a sample pot. which I'll put on in the brightest lightest section of the room.

Thanks Kelli, The rooms are for a Granny Flat , at the moment for my Granddaughter, she likes the white walls etc, with gray accents.

I've been passionate for 50 years for pale off white walls and ceiling, now I have to be game for other styles, but being so old now I want to get a modern look for the much younger generation.