M,
In my opinion, you are stepping down to use Hayward equipment... I apologize to all the Hayward lovers in advance...
If you are building a new pool, why in the world would you put in an old automation system... Although the EasyTouch is a great system, the Pentair IntelliCenter is even better and it comes with a build-in remote controller similar, but better than ScreenLogic.. All for about the same price..
An app can't do anything unless there is a system in place that can turn things on and off, move valves, control lights, etc...
If you use and maintain your water per the TFP process there is no reason to have a "Cupro nickel exchanger."... You are going to have a SWCG, so there will be not be any low pH and acidic tablets to destroy your heater..
That said, no matter what system you get, make sure the Automation, the VS pump and the SWCG are all the same brand.. It does not matter what brand you use for the heater or filter..
Good luck with you decision..
Thanks,
Jim R.