You still are missing the problem: The Astrologian is a healer that, by design, is intended to replace the White Mage or the Scholar in the standard WHM/SCH duo. As long as this is true, the class cannot stand on its own. The healers need to be made interchangeable to the point where any 2 healers would work all the time without directly out-competing each other.
I'd change quite a few things, but still keep a couple core tenants. The major changes, however, would be summed up as this:
- Remove the stances, replace them with mutually-exclusive buffs, one Diurnal, one Nocturnal, with different benefits and downsides unique to the AST.
- Redesign Synastry to be a permanent buff that does what it currently does, boosts healing directly on that target (by a smaller amount), and also heals the target for damage done, roughly around the rate a fairy does, for one target only (sanity cap so it doesn't turn into mega-heals).
- Make it so Royal Roads are given at random every time you draw, let spread save the Royal Road, Shuffle swaps the card, RR swaps the royal road, cannot pull what you just had, and cannot change both the card and RR effect.
- Adjust A.Benefic and A.Helios so that they are unique to the AST, but that the AST has at least 1 strong enough barrier, where "enough" is defined as 10% of an equivalent ilevel tank's total health (stoneskin).
- Combine Collective Unconsciouses 2 effects into 1 and increase its radius to be identical to Sacred Earth, but keep the Channeling effect. If it requires channeling, it better be the best thing you can cast for the entire duration.
- Redesign Celestial Opposition. As an idea, make it so that it gives the entire party the benefits of Synastry, perhaps even at 100%, for 10 or 15 seconds on a very long cooldown. Whether it boosts buffs and stuns enemies is irrelevant past this, but the idea is that it should be incredibly powerful for having an incredibly long cooldown.
Obviously, adjust all numbers (including base healing levels) as required to achieve balance. But for instance, for Diurnal/Nocturnal, Dirunal could make all base (Benefic, Benefic II, Helios) heals heal for an additional 25% potency every tic for 6 seconds (2 tics), stacking HoT, while Nocturnal could increase the mana cost of all base heals by 20-25% but also increase the potency by 50%. They both force the opposite onto a 1 minute cooldown and are personally on a 2 minute cooldown (or something like that).
The idea is to define the healer around Synastry as a mechanic instead of a cooldown, and make the cards random but powerful and a bit easier to use and, in doing so, make them a hair more consistent.
Remember, the class is a healer first and foremost, and it must be as good as the other 2 at it. This nonsense that people will just bring 2 ASTs can be designed out of the system such that it isn't a problem, so making the class actually competent should be the forefront of any changes.