I'm not one of the experts, but regarding the skimmer placement, I believe if possible you want them facing into the prevailing wind, so the wind will help push the floating debris into the skimmer. But as I'm sure you are aware, the wind changes rather often in Las Vegas. I seem to remember reading on here that a lot of people are now using two skimmers, which while costing a bit more for plumbing, might be a nice way to go, so that you can capture the two most frequent wind directions, so I'd consider having one facing westerly, and one facing northerly on opposite ends of the pool.
As for lights, the consensus seems to be it's best to point away from the residence, and not in the "swim lane" so you don't get blinded if you're swimming at night. Also a good idea to not have them point at seating areas if you can avoid that as well. I chose to go with led lights because I like the look of changing the water color at night.
You'd think solar heating would be a great option in Las Vegas. I've read some pretty negative opinions about doing this here. Most having to do with longevity, the cost of moving the water from the pool to the roof, leaking panels causing damage to the roof, and freeze issues over the winter. The other thing that seems to be that overcoming all of those negatives only results in the extension of a couple weeks on each side of the swim season as compared to using a surface bubble cover, and some supplemental use of the gas heater. Which all boils down to whether the cost is justified, especially if you've already got a heater for a spa. Now, that's what I've read on the internet (which is always right, right? LOL) as I have zero experience with it. When I discussed this with my PB, he was very non-committal about it, but suggested I plumb my system with stub outs in case I (or the next owner) chose to go down that road, which is exactly what I did. I figure I'll see how it goes over a summer without it, and go from there.
On decking...lots of options depending on your taste and budget. I looked at as many build threads as I could, saved pictures to show the wife, and we changed our mind several times, and in the end, decided this was a place where we could compromise, and went with a less expensive option to put money elsewhere. One thing on your design I would be wary of, is the part where you are showing a 38' x 8' strip of grass separated by 3' of deck to the water (bottom of your plan) In my last house, I had a pool with grass separated by a 3' walkway. It was impossible to mow it, without grass ending up in the pool, so I personally would never do that again. Unless you're planning to use artificial turf, which would then solve that problem..
