A home with no stairs can be as luxurious as one with many floors. It depends on the design and the materials used to construct and finish the home.

You can use natural stone like marble for floor but do not use granite for floor at all as it is very slippery when wet. As for tiles do not go for glazed vitrified tiles for the floor for the same reason. ( floor becomes slippery once wet and may cause mishap) Go for ceramic anti skid tiles that are specially meant for bathroom floor. For wall tiles you can use whatever you like and then decide over the matching anti skid floor tile/ marble. Double charged vitrified tiles are usually used for flooring in rest of the house.

I am assuming you haven't finalised your wall colours and colours of any other fixed elements. In case you have finalised your color scheme you would need to see which of these colours blend well or complement with that scheme. Assuming none of this info is available, then you could look at the neutrals which go with all colours. The white tile and the 2 colours at the end would be preferable. If you want color on the floor as well as drama, you can choose from the 2nd options from both sides or even the 1st from left.

Hello. As you rightly mentioned, there are lots of varieties of tiles available in the market today, including the wooden pattern ones. These designs are offered by almost all the leading tile companies. Well, the patterns/designs are usually on individual's preference, but a natural teak wood pattern would give a natural look as you requested. More than the designs of the tiles, the points that I would suggest to take care of before choosing a pattern is 1. It should not be too dark as it will make the room look smaller 2. It can have a decent amount of texture finish, but shouldn't be over board as it will be a hindrance to walk freely and also cleaning would be a pain. 3 The thickness of the tile, many good companies be of standard quality 4. Easy availability of the tile, in case you have to replace the broken tiles, they should be easily available. About matching the floor with your walls and ceiling, do not replicate what is on the floor (color/pattern), instead go for something lighter in shades (wallpapers or paints) for walls and for ceiling you can consider the wooden theme PVC panels, which are available in multiple colors.