Just trying to understand a little better. Reading the spell descriptions it appears that the Unified aego spell and the Unified symbol spell both do the same thing: give you HP, AC, and spell haste. But from all measures it appears that the unified symbol spells give less HP and less AC than simple aego does.
What am I missing?
The Aego line historically started as a combination of the three major cleric buff lines, Symbol (HP), Courage (HP/AC), and Holy Armor (AC). As it did not include a mana regen line, it stacked with certain self buffs, the big one of the time being the Paladin armor line.
The symbol line, on the other hand, stacked with the druid (or cleric, but then you'd just be using aego anyway) hp/ac buff AND, should you have the buff slots to use it (you probably didnt), the Holy Armor line, which lost a little ac to gain mana regen.
Current day, they do the same thing, but have the spell haste line tacked on as an addon.
If you have a self buff that gives mana regen, and hp/ac,or certain shielding buffs which give mana regen, the Aego line stacks with it where symbol + druid buffs will not.
As a Paladin, for instance, Commitment / Fernshade Keeper (Cleric / Paladin Aego) + Paladin Armor is 23 more mana regen, 279 more AC, and about 1k more hp than Symbol + Emberquartz (Druid skin), but Symbol + Emberquartz is 6k more HP and 123 more mana regen than Aego by itself, at the cost of 139 AC.