Interesting creatures. Here's my 2 cents.
Add darkvision 60 ft. to the SQ line, as aberrations and undead get it. Flight is listed on the SQ line, but not in the monster's description. I assume you are going with the beholder-style supernatural flight, so it would look like this:
Flight (Ex): An overseer's body is naturally buoyant. This buoyancy allows it to fly at a speed of 20 feet. This buoyancy also grants it a permanent feather fall effect (as the spell) with personal range.
Skills: I think the standard for the skills line would be "Speak Language (one language)", "Speak Language (two languages)", etc. Orbs with 5 ranks in Sense Motive get a +2 synergy bonus on Diplomacy checks, so for each I'd list Diplomacy +2 plus Cha modifier. The progenitor orb gets a +2 synergy bonus on Diplomacy, Intimidate, and Disguise checks when acting, so it should look like: Diplomacy +10, Disguise +8 (+10 acting), Intimidate +30.
Feats: Progenitor orb needs one more feat (5 feats at 13 HD).
Environment: Change to "Any aquatic, any mountains, or underground."
Advancement: Chage "As character class" to "By character class".
Lunars: I'd recommend changing the save DC to 10 + 1/2 the orb's HD + orb's Cha modifier. They will scale better this way.
Leather Lunar: Replace "subdual damage" with its 3.5 name, "nonlethal damage".
Platinum Lunar: Is the dispel magic a targeted dispel, area dispel, or the orb's choice?
All-Around Vision generally grants a bonus to spot and search checks as well as not being able to be flanked. Here's the general writeup:
All-Around Vision (Ex): Overseer orbs can ‘see’ in all directions, giving them a +4 racial bonus on Spot and Search checks, and they can't be flanked.
I would recommend changing "vulnerability to acid" to "acid vulnerability". Generally, "vulnerability to..." means that the creature takes an additional +50% damage from the energy type.
