Get the professional sander guys in to repair the living areas and kitchen but don't go too dark with the stain as it will kill the lovely grain in the matai. I'm thinking a couple of tones richer than the timber knots showing in your photo, definitely no yellow tone at all. In NZ stepping on to carpet especially in a kiwi winter is so much nicer than a cold floor board shock!!! A nice area rug for the lounge and you're done.

I haven't put engineered oak floors in my home, but I love the oiled look. What did you decide to go with?

Sanded and polished timber floors have a evergreen classic appeal that never goes out of fashion. Carpet and other floor coverings do have a tendency to have a style that is relevant to a particular period in time. Have you ever walked into a home and thought the carpet, lino or tiles were from the 60s, 70s or 80s? Natural timber floors never date and you can easily update the look of your home with warming floor rugs and furnishings. Carpeted homes may pose problems for Asthmatics and those that suffer from allergies. There are a few environmentally friendly coatings available if you do choose to sand and polish your floors. This link will offer some insight into your floor coating options. http://budgetfloorsanding.com.au/timber-floor-finishes/ All the best with making your decision

after watching my daughter and her husband agonize over the way their expensive timber floor has not held up well after 3 years, I would recommend tiles/wood look tiles with under heating. Their beautiful warm expensive floor looks like it always needs a clean and polish, not from neglect, they have cared for it well. One of the boards now has a slight and painful moan when it's stepped on :-( I grew up in a completely wood floor home and although it looked wonderful, my Mother hated it. ....and the mats ! Wood is a lot harder to maintain than tiles ,(no matter what the die hards say) the modern wood finishes are much better than they used to be.... But a piece of wood is rather arty no matter what it's used for and it does demand to be loved and cared for.....and if something goes wrong it's a lot more expensive to fix than sand and cement. Ultimately you have to be happy. BTW underheating tiles is warmer than timber :-)