Wow...I wrote a long post and it got deleted when I accidentally hit back in the browser....bye bye 30 minutes of my life.
So yes, $1000-1500 is more standard. You would want gas if you are going with a spa. I am not certain, but heard heat pumps are good enough for this area. If you need to raise the temp of the pool quickly (within hours) a heat pump won't be able to do that. It will take a heat pump days to get to the temp you set. I am not getting a heater as I get sun all day long and with a darker, pebble interior I "think" the water should be warm enough. Most of the issues with heat is more about retaining heat in the pool. Pool heat is mostly lost via evaporation, especially overnight. that is why some people decide to deal with the hassles of a solar cover or invest in an auto-cover ($$$$ $10K++ for starters).
As far as a design, you probably won't get more from A&S. They have some people that do 3D, but no in our area. In either case, Arista will do it for free so you will get a feel for it. Neither of them does what Monogram does with Pool Studio (search Monogram on Youtube to see).
What else...hmmmm...
SWG -> Definitely oversize, but make sure to buy total control components (item # 75003) if you skip the pH stuff. This may look like the DIG-220, but the DIG-220 cannot be added on to...in other words you cannot add the ORP sensor to it. Think about automation if you want it and if your equipment will all work together across brands.
Depth -> Get a tape measure and check different depths against you and your family's height while sitting, kneeling,standing and so on to get a feel for depths. With a sunself inside the pool (part of your 710) this will take up space and accelerate the slope in your pool so it won't be 3.5" very long.
Pool cleaner - TR35P is not a robot. It is a private lablel Polaris 3900 ->
The Truth About Pool Cleaners: What Your Pool Store Isn’t Telling You | Sunplay
Robots seem much better (onboard filter, navigation tech, etc). Pressure side vs robot is like a roomba vs a brush.
Decking -> Stamped concrete was something I considered. You should look into it as I have read people stating issues with how hot and slippery it can be. Also think about your design and how it will look when the concrete color starts fading, chipping or cracking. I feel the stamped concrete is a fad and question how I would feel about it in 10-15 years. You may feel otherwise, but that detracted me from it. I like the look of rock salt finished concrete, but to each their own.
Cover - I prefer mesh. I don't have a pool now, but grew up with one. The solid covers required a lot more pumping and raking to get wet leaves off. Maybe things have changed, but when we switched to a mesh cover it was far less maintenance.
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Oh, and as far as sunshelf placement...how will you use the pool? Do you want to swim laps? That may make you want to move the shelf out of the way and start with a 4' in the shallow end. I have small children now so didn't want to start too deep.
Also, a rectangle shape makes thing easier for pool cleaners (robots and pressure cleaners), cheaper for pool covers and easier to deal with solar covers, etc.