My advice is to ask them to see examples of finished pools with the various options. Salt finish to me can hold a lot of dirt and debris and be a pain to keep looking nice.
Most people that go for a color, go for a neutral earth tone to look similar to a stone color. Just keep in mind it's going to fade and end up lighter or washed out.
Textured helps hide imperfections and damage down the road. And yes, it's going to happen when someone drops something or drags a chair, etc.. It can also be hard on the feet after they're tender from being in a pool for while.
Broom finish is going to look like a city sidewalk with lines from the broom. So normally people end up with textured, stamped, or salt finished. Is stamped not an option? If you have a modern design, a rectangular grey slate stamp is usually a good option. Also give the ability to do some more modern design like grenerey through parts.
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