So a new blog entry was posted with that included an image of Astrologian along with 24 action icons on the hotbar.

I'm not sure how much information can be taken from the above image, but someone did point out that there are three actions with an MP cost in the four digit numbers. One of which appears to cost just over 2000 MP. Though that might not be that strange considering the MP cost of Black Mage spells are a little over triple what they are at level 50 (when idle). The most expensive spell on the list is probably Ascend with the other two likely being AoE heals.
Also I don't think all Astrologian actions are shown in that picture. Assuming they have close to the same number of total actions as the exciting jobs, by level 60 they should have a few on a third hotbar.
Actually I'm pretty sure all actions being shown on each job's hotbar are displayed in the same order they are learned. Using White Mage as a point of comparison, their first few spells go Stone, Cure, Aero, Cleric Stance, Protect, Medica, and Raise. If you go across the first hotbar for Astrologian the icons and associated MP costs seem to follow that pattern with the 7th action on the list being the most expensive.
Insert speculation that could easily be inaccurate:
Row 1:
Offensive Spell
Benedic
Offensive Spell
Draw
Lightspeed
Helios
Ascend
MP Restore?
Detriment
???
???
Dirunal Sect
Row 2:
Nocturnal Sect
Benedic II
Shuffle
Disable
Spread
Wheel of Fate
Royal Road
???
???
Synastry
???
???
I still speculate that there is another AoE heal aside from Helios and Wheel of Fate considering the way the latter of the two has more recently been described as an Asylum/Sacred Soil type ability, but until a source explicitly states that there is another AoE heal spell I'll assume it's just those two.