I regularly spend a few minutes (or an hour or two) just throwing together lists with one of the online list creator tools. I always find that I spend a lot more time making each rebel list than I do making each imperial list. My rebel lists also have a bit more variety and are, generally, more interesting.
In an effort to waste more time, I looked into the number of cards and unique pilots that each faction has all to itself. The count is:
Imperials:
-Pilots - 27
-Upgrades - 10
Rebels:
-Pilots - 28
-Upgrades - 28
Upgrades includes everything from bombs to titles. Pilots is limited to unique pilot cards. Anything that can potentially be taken by current ships in both of the factions was disregarded. This takes into account the upcoming Rebel Aces release as I think we now know all cards in the pack, but it does not include cards from the upcoming wave 5 release. I did not count any cards that are only available for huge ships.
As far as accuracy goes, it was difficult to find a complete source of which expansions came with which cards. There may be a mistake or this may be incomplete, but I wrote them down as I went, so it should be pretty close.
My own personal conclusion from looking at my lists is that there is a lot of opportunity for rebel builds to work off of synergy while my imperial builds are typically some variation of a tank and a flanker. That said, there is a huge difference in the number of options available.
I haven't looked into it, but does the larger number of options actually translate into more diversity in competitive lists, or are most of the cards used more for fun/quirkiness than for competition?
Imperial Pilots
Backstabber
Boba Fett
Captain Jonus
Captain Kagi
Captain Yorr
Carnor Jax
Colonel Jendon
Colonel Vessery
Dark Curse
Darth Vader
Echo
Fel's Wrath
Howlrunner
Kath Scarlett
Kir Kanos
Krassis Trelix
Lieutenant Lorrir
Maarek Stele
Major Rhymer
Mauler Mithel
Night Beast
Rexler Brath
Soontir Fel
Tetran Cowall
Turr Phennir
Whisper
Winged Gundark
Imperial Upgrades
Advanced Cloaking Device
Darth Vader
Proton Bomb
Proximity Mines
Rebel Captive
Royal Guard TIE
Seismic Charges
Slave I
ST-321
Stygium Particle Accelerator
Rebel Pilots
Airen Cracken
Arvel Crynyd
Biggs Darklighter
Chewbacca
Corran Horn
"Dutch" Vander
Etahn A'baht
Garven Dreis
Gemmer Sojan
Han Solo
"Hobbie" Klivian
Horton Salm
Ibtisam
Jake Farrell
Jan Ors
Jek Porkins
Keyan Farlander
Kyle Katarn
Lando Calrissian
Lieutenant Blount
Luke Skywalker
Nera Dantels
Roark Garnet
Tarn Mison
Ten Numb
Tycho Celchu
Wedge Antilles
Wes Janson
Rebel Upgrades
Blaster Turret
B-Wing/E2
C-3PO
Chardaan Refit
Chewbacca
Han Solo
Ion Cannon Turret
Jan Ors
Kyle Katarn
Leia Organa
Luke Skywalker
Millennium Falcon
Moldy Crow
Nien Nunb
Prototype Veteran
R2 Astromech
R2-D2
R2-D2 (crew)
R2-D6
R2-F2
R3-A2
R4-D6
R5 Astromech
R5-D8
R5-K6
R5-P9
R7 Astromech
R7-T1
Please let me know if you notice that I am missing anything.
Edited by Rapture