Lots of questions to be answered to give you more help:
1) is the spa standalone or integrated with the pool.
2) is there a spillover on the spa? If no, what is the proposed equipment for the spa and how are they going to integrate the spa with the pool?
3) Is there a separate pump for the spa, or integrated?
4) What types of configurations does the owner expect? Run spa, run spa and pool heater, run separate, run water feature etc.?
5) how many returns? Specifications on piping from returns to the pool?
6) are there jets or blower in the spa?
In general, one skimmer is not much, I'd get at least two, and face them into the prevailing wind. Returns can circulate water, but cannot overcome prevailing winds.
On the equipment side, I don't think you can go wrong with either Pentair or Hayward. I choose one and go with same/same equipment.
The easytouch has been obsoleted:
IntelliTouch and EasyTouch Officially Obsolete
I suggest the new IntelliCenter The IC has 100 schedule, can be updated using the internet and has phone control built in. I can't comment on the Omni logic...and would need to know more about what you want to control and how for someone like
@ajw22 to comment.
VSP: Get the largest VSP you can get. Will save money in electricity bill because you can move the same water at a lower speed. Like the Pentair Intelliflo or the Hayward Tristar VS 950.
Filter: Get the biggest cartridge you can get. Large allow you to run the entire year without cleaning. Lots of us like the Pentair Clean and Clear (at least a 420 or 520).
Heater: If you are going with Pentair, get a pentair mastertemp...it can integrate RS485 with the Intellicenter. Get the biggest you can get.
SWG: I would get a normal salt cell, pentair or hayward, unless you are required by law to use low salt (may be the case in CA).
Post up more requirements and others will chime in...