@ jmm1837....I think you are very courageous answering this exceedingly difficult question! The answer above is probably something like I would say. I've been an artist for many, many years but not famous, not well known although I've sold many works and can turn my hand to any style, my preference for my own interest is "in the style of Turner" I've written a book on Colour Mixing for artists which is a teaching text. I'd say that there are not many questions I cannot answer about Colour....with the exception of these kinds of questions....to which, in my opiion, I concur with you, there is no one answer. I often thank my lucky stars that I live in a 1900s timber home that resembles a log cabin inside....Queensland Hoop Pine VJ ceilings, walls and floors, silky oak arctic glass casements, Hoop Pine or Silky Oak doors...and the only colour is the furnishings...and I can't even decide on these! So - to ask me "What Colour" to paint the walls of a house for sale really jangles my brain! I've never had to resolve that dilemma here...I'm not going to paint it...ever! So how to assist in this dilemma? As you explained, jmm1837, older character home -use some colour, newer home with clean lines - light neutrals...so far I agree. BUT...I was watching one of those TV home reno shows...A couple who could not agree on any colour for anything and a designer ,( bless her persevering, understanding, patient, kind, and dog-with-a-bone determination) trying to help them do a reno. I was suddenly inspired ! I had encountered once a colour that contained all colours, that would 'go with' all colours but yet could be described as Lilac but wasn't...and Neutral but wasn't. Thinking "lilac" I think of demure, age appropriate attire and lace...so not very decorator inspiring. The particular LILAC they used for skirting boards, trim and door jams alike worked like magic! I can see readers screwing up their noses and almost hear others saying ERK...That was my reaction when the word Lilac was mentioned.... I did not take any notice what the brand was, I was too astounded by the finished effect. It wasn't Lilac, it wasn't grey...it was a colour but it was a neutral ....and it reflected a different shade depending on its position in the room and its proximity to soft furnishings. So....what's my solution? With both styles of home...think neutral with a tendency to the palest, palest of violetey greys maybe complemented with a drop of ochre ever so subtle...So a neutral to the eye but a colour depending on its position in the house, and keep it all the same, no accents...I believe the light and adjacent furnishings will work with such a hue. Colour is Magic. I'm convinced more than ever that it can morph into any hue. Just some thoughtful reflections from a colour fanatic.

Whisper white is so very barely warm, I think it would achieve what you are after as it is often used in cool colour schemes. You can view the full range of Dulux whites on the attached link. If you click on a colour it will give you the break down of red, green, blue content for each colour. Just remember the colours on the screen will look different on your walls as the computer uses subtractive colour and you'll be painting with additive colour. http://www.dulux.com.au/specifier/colour/colour-atlas

Well, I'll be 1st to comment(might get ball rolling for ya!). I'm a painter, 35 yrs. Is the Dulux sw1e1? Wish you had pics of swaths side by side. But that's ok. Imo, they're both going to be just fine. I very highly doubt you would go wrong either way, you'd have no regrets. After all these years I know that white, in just about any shade, is going to work with just about any furniture. Except maybe white furniture! I'd have to see the furniture to give more detailed opinion though. If were me, I would want the floor to be dark(ish) though, not light(ish). Try to slap a few pics of some of your stuff on here and maybe you will get some better opinions than mine! And more detailed as well. Either way, I know you're fine with either of the 2 paints. Imho, of course!

What Dr Retro says above. The short answer is it would be rare to use the same paint throughout as you’re dealing with a number of different surfaces & end uses. Paints are designed for each specific application. Ceilings: use matt ceiling white, or if you want a coloured ceiling, tinted ceiling white. If you‘re doing a ceiling feature a satin finish could be used as long as the ceiling’s in good condition. If the ceiling’s in average condition some professional painters use an oil based undercoat instead of water based ceiling white. Walls: use water based satin finish, some brands call it low sheen. Walls in wet areas: depends how good your ventilation systems are in these rooms, sometimes worthwhile to use the lowest level of gloss paint (water based semi gloss) but as Dr Retro said above the higher the level of gloss the better condition your walls need to be in. If you have areas of new plasterwork, or cracks & holes that have been filled, apply a sealer binder over these areas before top coats, or the plaster patching will show through your top coats as it takes up the paint differently from the non plastered surfaces. On new woodwork use an undercoat then your preferred gloss level ie. semi gloss, gloss, or high gloss only where the surfaces are perfect (very rare). Some paints are promoted as primer/undercoat/topcoat all in one. I’ve found the finish is better using undercoat, then top coat, but that’s my personal preference. On existing/already painted woodwork: use undercoat on any filling/patching, then same topcoats as for new woodwork. If the existing colour is dark & you’re going to a light colour undercoat is recommended, or many top coats will be required to cover the dark original colour. Bare wood with a high tannin content is best sealed to avoid tannins bleeding through to your topcoats.