1. The photos I posted purposely have no filter applied and show the true color. Green undertones are only visible in certain conditions. During sunsets, the yellow certainly brings out a touch more green/lagoon feel. The Moraine isn't likely to make pool water the color of a bottle of Windex
2. Yes, but keep in mind the deepest part of pool is 5 feet (next to the two drains) so if you have a deeper pool, you can expect deeper blues
3. With a relatively shallow pool, it's tough to judge. Certainly there are finishes with deeper blues, and others with more green.
@Nikilyn has posted a lot of beautiful pictures of her build listed as "Micro Pebble Aqua White" but I believe it might actually be "Aqua Blue" since the plaster has blue dye in it and the base mix for White does not specify any pigment or dye in the mix (see attached pdf). Comparing our pics side by side should give an idea of the differences in water color one could expect if you're torn between blues.