I'd be inclined to stick to similar or darker woods with a similar warm tone. The furniture doesn't have to match the floor, of course. In my last house we had spotted gum floors and mainly blackwood furniture (with a few pieces of mahogany). Looked great, especially with a few rugs to provide some visual separation between floor and furniture. Wood floors provide a pretty flexible backdrop: just don't mix too many different finishes with them.

I'm a big fan of black as both a statement and accents (e.g. high gloss kitchen bench tops and splash backs, matte black main vanity and floor tiles, lounge, Art Deco sideboard etc). It seems to collect and show dust on the floor more than most, and can suck a lot of light depending on its location and application. Why not 'test drive' your black flooring idea (cheaply) with some wide black gardening plastic from a hardware store for a few weeks before committing to an expensive and potentially irreversible step. The plastic can always be used as a drop sheet later! You may find that having your black in furniture (such as Japanned table or sideboard) and accessories, together with the odd touch of jarrah, may be the look and colour balance you seek.

In both pictures , the upper cabinets look a cream and the below bench ones look white ? Might be a flash or similar , because that doesn't make sense to me . I hate grey at the best of times , and this kitchen has gone for the blandest shade of grey for the walls too , and I'm not sure if there is a grey tinge to the tiles , but it looks like there may be . Like dreamer , I'd go a reasonably colourful rug , and 2 or 3 brighter coloured benchtop appliances , because I suspect most potential buyers will want to change 1 or more aspect anyway . The other thing is that you said the tiles are right through the house -- tiles are sort of expected in a kitchen , not in a lounge or bedroom . So if you do a nice floor in the kitchen that really suits the space , not only will a potential buyer be thinking they want to completely redo the kitchen , but it also highlight the tiles elsewhere too .

Hi, HU-932380478, do not use glue and sawdust as it cracks and falls out as soon as your floorboards move. You are best to use a flexible acrylic Calking Compound like what is used on boat decks. This is applied into the gaps wet, overfilled and allowed to dry, where this may take up to 7 to 10 days with large gaps. Once dry and hardened you can then sand it back with Drum Floor Sander and then fine finish with a large orbital Plate Sander. With the project in the image below we used Fullers Calking in a Cedar colour. Hope this helps, Malcolm.