About your question about sourcing some of your own internal fittings. It is best you discuss this with the builder early on. Usually, the builder's contract will specify an allowance for particular fixtures. However, some may specify actual brand and model of fittings ie taps, toilets, sinks, etc in their quote, and they may or may not allow you to vary this. IF you are happy with those specified fixtures and you think the allowance amount is reasonable, then you can go with it. Otherwise, any changes or variances need to be discussed with builder, and it is very important this be discussed upfront and before any contract is signed. Some building contracts may also disallow some variances. In any event, carefully read the contract so you completely understand what you are agreeing to, and discuss any and all parts where you are not in agreement so these issues can be ironed out. Also, and this is my own experience and opinion, but I advise specifying in the contract the completion date AND if the build is not completed on time then what happens (consider that you may be paying interest on your mortgage, be financing a bridging mortgage, etc. and/or you may also have already sold your home and then have to pay rent until the build is finished). If you are in agreement with builder to source some of the internal fittings yourself, there are any number of suppliers and sources to investigate, and this might be a good way to keep your budget in check. There will be Houzzers who are experienced at this and can provide you with ideas. Just keep in mind that you will have to have all fittings READY and ON SITE when the tradesmen require them, otherwise you will be holding up the build and that is going to cost YOU money.

While I'm with Siriuskey regarding real timber, it would always be my choice, I recently saw a brand new house with very similar tiles down the long, wide hallway into and throughout the open plan kitchen and living area. It could be that it had a north facing, predominately glass wall allowing the sunshine to flood the room, but I was surprised just how good they looked. Perhaps you could check out the real estate websites to find an open house near you to check for yourself? I do think the quality, of both the tile and the expertise of the person laying the tiles, could make a huge difference also. In the meantime, perhaps your partner may see the light before the final decision is made ;)

Porcelain wood look tiles look good. They are low or no maintenance compared to hard wood. It would be personal preference of yours to run them through the whole house. I would suggest that you rethink the order of your flooring and kitchen renovations. If you lay tiles around your existing kitchen, then when, come the time to renovate, you may change the kitchen layout, therefore tiling to match new kitchen would be troublesome. Eg: matching colour lot?Will the tiles be still available? Can I suggest, to buy enough tiles for kitchen area when purchasing now. This may save any problems in the future. Can you post a photo of your current kitchen, so we can give suggestions on colour of porcelain tiles.

The whole place has that 'of a certain period' look , but I suspect it can be done . The 'reverse' side of the bench in pic 1 has to go -- it looks cheap veneer that has overstayed its welcome ! Black or white gloss Formica or similar would lift that . The lino would need be modernised -- maybe tiles , maybe just 50 year newer lino , or wood planks would look mutual and modern , and reference the benchtop too . The wall tiles ditto -- remove and replace . Gloss white or black or charcoal . Or a colourful splashback , either the full width or maybe as a centrepiece 1.5-2 metres long , in a red or green or yellow or similar . Above that paint in ( I shiver as I write this ) grey . Maybe a 'frieze' of contrasting but complementary subway tiles , attached vertically to add some bulk . Ordinarily , I'd suggest cupboards or even shelves or a display cabinet above that , but anything added would look so out of place it would be hard to pull off , unless you matched the timber benchtop , and that would be difficult . And presumably change the cupboard handles -- a trendier stainless or chrome design would tie in with the sink unit .