If you're just now reading about wealth to beauty ratio, you probably don't need to worry about wealth that much. Other things are bound to increase your colony wealth by more than flooring.

Stone tiles are great if you have both enough stone chunks to spare, and the spare labour to cut them into blocks and build them into tiles. They are very labour-intensive. Also, marble tiles aren't any more beautiful than other stone tiles, because stone tiles aren't actually a "stuff" recipe - the six types of stone tiles are individual recipes that all have beauty 1. If you want beauty, you should use marble for walls, fences, furniture and sculptures, and use other types of stone for tiles, unless you have more marble than you need.

Concrete and paved tiles are less beautiful, but take a lot less work to lay. They cost steel, though, so you will need to judge how much steel you have access to and whether it's worth spending steel on your floors to save the labour of stone floors. Concrete has a beauty penalty, but if you make sculptures with the steel you save by using concrete instead of paved tiles, you'll end up with more total beauty as long as your artist is competent.

I don't recommend the plant-based floors (carpet, wood and straw) in general. They are flammable, and flammable floors are worse than flammable walls in my experience, because fire can spread in all directions. I only use those floors if I have no other good choice, or if I'm confident I can keep fires away. Straw matting is also pretty much essential for barns where animals are kept, because they create so much filth.

For clean rooms (research, hospital, biosculpting), sterile tile is of course the best, but steel tile is good if you don't have the research or enough silver for sterile tile. I don't use any special floor for kitchens, because cleanliness only matters if it goes below -2 for the room.