Although the rule says where tile abutts a dissimilar material, it's also industry standard to grout the tile to the drain.

I used Navelli Carrera Star for my main bathroom where we have a shower/tub combination so I have not yet needed to tile the shower floor. However, I purchased enough to do my master bathroom with a shower only. One of the options we're considering is to cut the 12x12s down to a size small enough to do the shower floor. The edges of the tile are very square so this should work out well. I already have a great deal of scrap tile (smaller than 6" wide) that I hate to toss out from the main bath remodel. When I purchased the tile about 6 months ago, I do not believe Daltile offered a mosaic size in the Navelli Carrera Star. Alternatively we've considered doing a river rock floor, or some sort of plain white mosaic, or even real marble mosaic.

I think matching the colors would be appropriate... Snow White and bright white are all preference based decisions... I would probably research manufactures for grout so you can make an educated decision Grouts are generally classified as sanded (cementitious) or unsanded. Both can be used indoors or out and on walls or floors. Use sanded grout for grout joints 1/8 inch up to 5/8 inch. Use unsanded grout for grout joints up to 1/8 inch. Grout is available premixed and ready to use or in powder form (mixed with water as you need it). If you use powdered grout, take care not to use too much water when mixing as this could weaken the grout. Read and follow the product instructions carefully. Acrylic grout is an option for wet areas. It's intended to be mildew-resistant and retains its color well. Epoxy grout is perhaps less DIY-friendly than the other grouts available. It's a common choice for countertops due to its hardness. Epoxy grout doesn't need to be sealed Regarding color choices ... Use grout to match or contrast your tile color – the choice is yours. Unless sealed, lighter colors often show stain more easily. Darker grouts may fade over time. Make sure your grout color can be used with your tile. More porous tiles could absorb coloring from the grout. Tintable grouts are a newer option to pre-colored grout in indoor applications. Tints are added to a light or dark grout base for a custom color. Sealing grout as a final step prevents staining and keeps out moisture. Make sure you get the correct sealer for your grout and that the grout has cured before you apply it. See the grout package label for details. Good Luck !! Regards, Mario MSDG www.msdg.design

It is the best estimate I have heard for the tile you chose.