I'm such a big fan of this idea that I'll mention it again with some new suggested signature abilities.

New versions of the main rebel characters should be released two at a time (e.g. Luke/Leia, Han/Chewie, R2/3PO). Then the version of one character (e.g. Luke) grants a signature ability via SA to any version of the other character (e.g. Leia) and vice versa. At the same time, the new versions have the signature abilities built-in. As such, it makes it worthwhile to play a new version of one character with an old version of another character.

I've suggested some signature abilities in the past, but here are a few more. (I like the idea described above more than I'm committed to any specific signature ability.)

Chewie
That Goes There: Adjacent non-living allies that are defeated are considered Broken instead of defeated. Broken characters are not removed from the battle grid and are considered objects: 0 HP, provide cover, are considered activated, do not count as adjacent or a legal target, cannot score victory points, do not block movement. Broken characters may be repaired, but remain activated when repaired. If this character is defeated, all Broken allies are defeated.

Leia
There is Another: If an ally with a Force rating is defeated, this character gains a force point. If an allied Luke is defeated, this character gains all of Luke's Force points and may spend force points twice per turn.

R2-D2
Beep Chirp: Replaces turn; a door within line of sight is opened until the end of the phase.

C-3PO
They're dying, Artoo!: If this character is not activated and has line of sight to an ally who is about to be defeated, the ally is not defeated and instead has 10 hit points (20 hit points if this character is adjacent to R2-D2). This character is considered activated.

Today, this a new version of Mon Mothma:

New Republic

Mon Mothma, Chief of State
Cost: 15
Hit Points: 30
Defense: 11
Attack: 0
Damage: 0

SA:
Unique
Affinity: This character may be in a Rebel squad
Booming Voice
Impulsive Tactician: If a Unique allied character is defeated, for the remainder of the skirmish you can add +2 to the initiative roll. (These bonuses stack.)

CE: Allies gain Avoid Defeat

Cool ideas flyerman! While were on the subject of imperials...

Sate Pestage
Carnor Jax
Grand Moff Trachta
Imperial Warlord Zsinj
Moff Kadir
General Tagge
Admiral Motti
Raith Sienar
General Skosef

Just a few i thought of

Imperial

Imperial Warlord Zsinj
Cost: 31
Hit Points: 60
Defense: 15
Attack: 2
Damage: 10

SA:
Unique
Tactician +4
Project Funeral: Replace attacks: Once per skirmish, choose a Non-Unique ennemy with legal target rule and another ennemy regardless of line of sight.
The first character chosen joins your squad until the end of the skirmish, gain Assassin and Accurate Shot against the secund chosen enemy.

CE: Non-Unique Imperial follower within 6 squares get +2 Attack and +2 Defense. Raptors and Imperial Navy troopers gain Avoid Defeat.

"This man has a special talent" General Han Solo

Raptor Soldier
Cost: 9
Hit Points: 10
Defense: 15
Attack: 5
Damage: 20

SA:
Close-Quarters Fighting


Raptor Commando
Cost: 15
Hit Points: 20
Defense: 15
Attack: 7
Damage: 20

SA:
Stealth
Close-Quarters Fighting

To finish with Anti-Sith conspiracy (see Moff Kadir and Grand Moff Trachta)

Imperial

General Skosef
Cost: 25
Hit Points: 50
Defense: 17
Attack: 10
Damage: 20

SA:
Unique
Sniper
Anti-Sith conspiracy:
Characters named Palpatine or Vader costs 2 less when in the same squad as this character and are considered as being Sith only for purposes of special abilities whose name contains Sith.
On an initiative roll of natural 1, this character joins the opponent's squad until the end of the skirmish.

CE: Imperial followers with Proximity Mines gain Mobile Attack and Self Destruct 20. On an initiative roll of natural 1, Allies with Self Destruct are defeated.

Today, i propose you Imperials from the Death Star (more classical)

General Tagge
Cost: 21
Hit Points: 40
Defense: 17
Attack: 7
Damage: 10

SA:
Unique
Opportunist +20
CE: At the end of this character's turn, 1 Non Unique Imperial ally within 6 squares can make an immediate attack at +4 Attack and +10 Damage and then move up to its speed.


Admiral Motti
Cost: 23
Hit Points: 40
Defense: 16
Attack: 6
Damage: 10

SA:
Unique
Merciless 30
Affinity: Allied characters with a Force rating cost 1 more when in a squad with this character

CE: Non Unique Followers within 6 squares gain Charging Fire.

Poopdog91, the last one for you

Imperial

Carnor Jax
Cost: 41
Hit Points: 120
Defense: 22
Attack: 15
Damage: 20

SA
Unique
Melee Attack
Twin Attack
Palpatine's Bodyguard

Force Powers
Force 3
Force Thurst
Sith Rage

"But I want to see all of you dead! That—and the Force—will insure my success!"
Carnor Jax

Cool characters flyerman! Thanks for putting some stats to the guys I want to see

Characters whose name contains pilot count as pilots too, so the first part of Fel's commander effect doesnt matter.

I want a luke with bravado. It really explains how he managed to go up against vader in the end.