Originally Posted by BuckettMonkey
In my opinion, the existing list of deities is already quite complete and does not need to be changed.
After all, it's better to have a small list of gods whose choices really affect the game than a huge list with no distinction.
However, I wouldn't mind playing as a cleric of Cyric or Eldath.
Originally Posted by 1varangian
It would be cool though if there were enough domains so all deities would have at least two to choose from.
Unfortunately, this is unlikely to happen.
Even after so many rulebooks, many deities (like Talos and Tempus) only received one domain, and this is unlikely to change.
In general, speaking about deities and domains, we can refer to the first edition of the Pathfinder.
The first edition gave a lot of archetypes, one of which was the separatist. "A radical cleric, unsatisfied with the orthodoxy of her deity’s teachings, forges her own path of defiant divine expression". This archetype allowed the cleric to choose a second domain not from the deity's domain list. By the way, this second domain cannot be an alignment domain that doesn’t match the cleric’s of they deity’s alignment.
Probably something like this can be implemented in the game. Like, cleric of Bane/Bhaal with a trickery domain, cleric of Tempus with a tempest domain, etc.
Well it's ok Clerics don't get a lot of flexibility. I think it fits the class since their powers come directly from a god that represents something very specific.

One could argue that all Clerics getting Guiding Bolt (a radiance spell) is already stretching it too far. Clerics of Shar or other dark gods should get a similar attack dealing Necrotic damage.

I think Clerics would be cooler if their universal spell list would be much more narrow and only comprise of very generic stuff like Bless or Cure Wounds. And then the Domains could be expanded to play a bigger part of their power repertoire. So Clerics would reflect their faith more accurately and have powerful theme-appropriate spells other Clerics don't get.

In BG3 it's odd any Cleric of any faith can use Create Water to call down rain, but Wizards can't. It's an elemental spell which seems much more of a Wizard thing to do. So it should be reversed, really.