As I think more about it, it actually kind of makes sense for them not to include Helios in the express, at least at the start.
They don't want to gut occupancy at the other hotels, and want to keep encouraging people to visit the older parks as well.
So lets say the other three express hotels cost relatively the same per night as Helios:
Helios - attracts those who want excellent access to
Epic, and to stay in a new upscale hotel (=focus on the new experience)
----which if express were included would encompass everyone who used to choose all of the other 3 express premier hotels, but that's way too much demand for the new hotel.
But without express included, some of those demographic will still elect Helios, but others will go to the older hotels.....and thus also the older theme parks to make use of their incentive.
I'm betting Universal is fairly sure they will have enough people in the first camp (wanting the new glitz/access to Epic) to still fill Helios even without those who will stick with their usual place due to wanting Express, which gives incentive to utilize the older parks/options as well.
- random question - does anyone know if Helios will be part of the pool sharing????