Here are just a few thoughts I've had on some of the pieces I wanted (I don't have much experience with customs, so my stats and cost might be off:
Anja Gallandro 27 Fringe
Hit Points: 80
Defense: 17
Attack: 9
Damage: 10
Unique
Twin Attack (Whenever this character attacks, she makes 1 extra attack against the same target)
Melee Duelist (+4 Defense when attacked by an adjacent enemy)
Lightsaber (+10 Damage against adjacent enemies)
Bravado +10 (+4 Attack and +10 Damage against an adjacent enemies with a higher point cost)
Parry (When hit by a melee attack, this character takes no damage with a save of 11)
Gambler's Luck (Once per turn, this character can reroll an attack, adding +4 to the result. If the attack misses, this character takes 10 damage.)
Spice Addict (If this character has less than half her hit points, when she activates make a save of 11; If the save is successful she gains +2 attack. If she fails, her activation immediately ends and she gains -4 Defense.)

Luke Skywalker, Fallen Jedi 45 Imperial
Hit Points: 110
Defense: 20
Attack: 13
Damage: 20

Unique
Melee Attack (Can attack only adjacent enemies)
Twin Attack (Whenever this character attacks, he makes 1 extra attack against the same target)
Djem So Style Mastery (Whenever this character is hit by a melee attack, make a save of 11. On a success, this character can make an immediate attack against that attacker with +10 Damage.)
Flurry Attack (Whenever this character scores a critical hit, he can make 1 immediate extra attack)

Force 3
Force Renewal 1 This character gets 1 Force point each time he activates
Surprise Move Force 1; Once per round, after initiative is determined, this character can immediately move up to his Speed before any other character activates
Force Push 2 Force 2, replaces attacks: range 6; 20 damage; push back target 2 squares if Huge or smaller
Lightsaber Defense Force 1: When hit by an attack, this character takes no damage with a save of 11
Lightsaber Reflect Force 2: When hit by a nonmelee attack, this character takes no damage with a save of 11 and the attacker takes damage equal to the prevented damage; save 11
Dark Temptation Force 1: +4 Attack and +20 Damage until the end of this character's turn. At the end of that turn, make a save of 11; if this save fails, this character joins the opponent's squad until the end of the skirmish.

Luke believed the only way to defeat the Dark Side was from within. He was wrong...

Morgan Katarn 15 New Republic
Unique
Affinity (Characters whose name contain Kyle Katarn may be in your squad Regardless of Faction. This Character may be in a squad with a character named Kyle Katarn regardless of faction)
Light Spirit (Ignores characters and terrain. Cannot open doors. Cannot attack or be damaged, and does not count as a legal target, the nearest enemy, or adjacent. Not subject to commander effects. Does not provide cover. At the start of the skirmish, choose a Unique allied character with a Force rating. That ally gains Force Renewal 1 and Mettle while within 4 squares of this character. This character is defeated if the chosen ally is defeated. An enemy within 6 squares can spend 1 Force point to defeat this character; save 11. This effect replaces that enemy's attacks.)
Kyle's Mentor (This character may use Light Spirit to target a character named Kyle Katarn even if that character could not normally be targeted. That character gains Force 1 and is considered to have a Force Rating)

@ andy, I had a similar idea a while ago though I made him a bit weaker. I know he was a strong jedi master at that point by I made this one as a renewed apprentice of the dark side. I would love to see him, would be a very neat addition to Imps.

Luke Skywalker Sith Apprentice 36
Hit Points: 70
Defense: 18
Attack: 9
Damage: 20
Special Abilities
Unique
Melee Attack (Can attack only adjacent enemies)
Double Attack (On his turn, this character can make 1 extra attack instead of moving)
Rapport (A character whose name contains Imperial Sentinal costs 10 less when in the same squad as this character.)
Turn to the Dark Side (Replaces attacks: range 6; 20 damage to 1 target with a Force rating. The target can choose to negate this damage and instead make a save of 11; if the save fails, the target joins this character's squad until the end of the skirmish.)
Force Powers
Force 2
Force Renewal 1 This character gets 1 Force point each time he activates
Illusion Force 1: When hit by an attack, this character takes no damage unless the attacker makes a save of 11
Improved Illusion Force 2: When hit by an attack, this character takes no damage unless the attacker makes a save of 16
Force Lightning 1 Force 1, replaces attacks: range 6; 20 damage
"And now, my young apprentice... Your father is dead. Have you come to join me? Will you take the place that rightfully belongs to you–at my side." ―Palpatine

I like to see an ability that lets you 'tag' stealth or cloaked characters.

Something like, if this characters attack hits (or maybe just when the attack) a character with stealth or cloaked, the target character loses stealth or cloaked until the end of the round (maybe save 11 to avoid, maybe not)

+1 for these characters

It would also be awesome to see:
More Null ARCs
Corr, Republic Commando
Yayax Squad
Other Mandalorian Training Sergeants (Walon Vau, Mij Gilamar, etc.)
Some of the Republic Commandos that became Imperials (I can not remember their names...)
Some Aiwha-bait would be interesting (Kaminoans)

Sidenote: Will this set be coming out around GenCon time?

Republic: C3PO
Qui-Gon Jinn Force Spirit

New Republic: Chewbacca


Imperial: Luke Skywalker ( Evil variety that briefly turned to the Darkside in the comic "Dark Empire" )
Cloned Emperor

Also I just read Revan and would love to see:
Sith Emperor (RM Emperor Palpatine)
131, hp 160, def 24, ATk 0, dmg 0
SA
Unique
Melee Attack
Master of the Dark Side (damage from this character's force abilities cannot be prevented or redirected)
Force Fury 17
Puppet Master
Doctrine of Fear
Avoid Defeat
Force 3, force renewal 3, master of the force 3
Force Bubble
Force Defense 
Force Throw Object (force 2; this power affects characters with force immunity. Replaces attacks, sight, 40 damage to one enemy and each adjacent character, save 11 for half damage)
Burst Lightning
Drain Life 3 (Force 3, usable only on this character's turn: range 6; 20 damage to target living enemy and each adjacent living enemy, save 11. Remove 20 damage from  this character for each enemy affected in this way)
Dark Aura (Force 1, replaces attacks; For the rest of the skirmish, this character gains the following Force ability: Enemy characters within 6 squares get -4 to all saves)
Surprise Move

Commander Effect
Sith characters in your squad may spend this characters force points, they still may not spend force points more then once per turn or combine their own force points with those of The Emperor.

Darth Scourge (RM Massassi Sith mutant)
Cost 52, HP 110, def 19, atk 12, dmg 20
SA
Melee Attack
Double Attack
Dark Armor
Juyo Style (this character scores a critical hit on natural 19 or 20. Whenever this character scores a critical hit, make a save of 11, on a success this character can make one immediate attack)
Cleave
Force 1 force renewal 1
Master of the force 2
Force Leap
Lightsaber Throw
Lightsaber block
force fear (force 2; until the end of this characters next turn he gains the following force ability, all living enemy characters within 6 squares have -4 attack and -4 defense and this character gains +4 attack and +4 defense)
Use The Force

just thought about this, but with the streak of sith lords we got in v-set 3, why not do ajunta pall(for those who don't know, he was one of the first jedi to turn to the dark side, and if I remember correctly, one of the first sith to exist)

Don't know if this has been mentioned but I'd like to see a mini set based on The Old Republic. My top wants would be:

Satele Shan
Jace Malcom (With an ability like this; Chain of command: This character is treated as a follower for the purposes of commander effects for characters with a higher point cost than him.)
Darth Malgus
Lord Scourge
Nico Okarr

I think it would also be sweet if we had one or two companion characters like Khem val or Aric Jorgan.
As for non uniques:

Havoc squad commandos
Revanite

That's what comes to mind off the top of my head.

Here is my take on Skywalker from Dark Empire:

Luke Skywalker, Dark Apprentice
Cost: 50
Hit Points: 130
Defense: 21
Attack: 15
Damage: 20

Special Abilities
Unique. Melee Attack. Double Attack, Twin Attack
Dark Apprentice (+4 Attack and +10 Damage when in a squad with a character whose name contains Emperor Palpatine)// Yeah, I know that WotC screwed up "contains" part, but we all know what I meant
Conflict of Interest (Each time this character attacks enemies whose name contain Han, Leia or Chewbacca, he must make a save of 11. On a failed save he can't attack the target)// This might need some work, but the idea is, that when he makes a Twin Attack against let's say Leia, he must make save before each of his attack

Force Powers
Force 3
Force Renewal 1
Master of the Force 2
Lightsaber Defence
Force Grip
Force Sense

Conflict of Interest is an interesting idea...but I think you are right that it might need work...I do like the idea of him hesitating when confronted by his friends though.