So I made a few minor changes, mostly to skills. She's pretty much done minus gathering the backstory fragments into a cohesive whole.
She's got 1pp left over, I'm leaving it open pending a GM response (when you're up to it, no rush) to the following question:
Considering that the aliens rule the planet, would the Connected feat be at all useful?
[sblock=Siren]
Ondina Naiad AKA SIREN - PL 10 (150 pp)
Abilities: 16pp
STR 10 (+0)
DEX 14 (+2)/18(+4)
CON 10 (+0)/14(+2)
INT 10 (+0)
WIS 14 (+2)
CHA 18 (+4)
Combat : 0pp
Defense: 22 (12 Dodge)
Toughness: +8 (+2 con +6 Protection),
Base Attack: 0
Initiative: +8
Saves: 22 pp
Fort +10 (6 base + 2 con + 2 Enhanced)
Reflex +12 (6 base + 4 dex + 2 Enhanced)
Will +14 (10 base + 2 wis + 2 Enhanced)
Skills: (76 ranks=19pp)
Athletics(+16/12), Bluff(+14/10), Diplomacy(+14/10), Escape Artist(+12/8), Handle Animal(+12/8), Notice(+12/10), Perform:Sing(+14/10), Stealth(+12/8)
*+4 to checks where attractiveness matter*
Feats(20): Animal Empathy(Sea Creatures), Attractive, Benefit(Atlantean Royalty), DodgeX12, Environmental Adaptation(Underwater), Fascinate(Perform), Favoured Environment(Water), Improved Initiative, Uncanny Dodge(Mental)
Powers: 73pp
Atlantean Container: [Descriptor: Racial, PF: Innate] (11pp)
-Comprehend Rank 2: Animals(Speak to and understand), Flaw:Sea Creatures only(-1) - 2pp
-Immunity Rank 3: High Pressure, Cold Environments, Drowning - 3pp
-Super Senses Rank 3: Sonar(Accurate Ultrasonic Hearing) - 3pp
-Swimming Rank 2: 5 mph - 2 pp
Psychic Array: [Descriptor: Mental, ] (45pp)
-PRIMARY: Mental Blast Rank 10 - 40pp
-Illussion Rank 10(Visual & Auditory, PF

rogressionX4[100']) *3/rank+4=34* - +1pp
-Emotion Control Rank 10(Dynamic) *2/rank=20* - +2pp
-Telepathy Rank 10(Dynamic) *2/rank=20* - +2pp
**Can use either Mental Blast, OR Illusion, OR emotion control + Telepathy**
Atlantean Armour: Device Rank 4[Hard to Loose] (16pp)
Protection Rank 6 - 6pp
Enhanced Abilities: Con+4, Dex+4 - 8pp
Enhanced Saves: +2 Fort/Ref/Will - 6pp
Drawbacks: Vulnerable to heat(Complication?)
Tradeoffs: +2 Defense/-2 Toughness
COST: 16 Abilities + 19 Skills + 20 Feats + 72 Powers + 0 Combat + 22 Saves = 149/150
[/sblock]