I just bought in a week ago, and so far i have TFA, Original Core sets, a T70 expansion, a yt2400/1300, A/B wing expansion and the Rebel Aces pack. What do I buy next or should I buy next? I'm exclusively a rebel player if you couldn't tell lol. Thanks in advance!
What next?
MOAR A-WINGS!!!
Maybe that's just me.
A Y-Wing or an X-Wing expansion would be my suggestion. Perhaps a HWK-290.
Definitely K-Wing! Turrets, unusual load out options, and TLT. 
Was thinking of getting a Kwing just for TLT heard its a really good card
What? No Y-Wings? Sacrilege!
And another terrorist is born, fear not citizens the imperial navy stands ready to punish this foul miscreant and his kind!
Welcome to the game and the forums, first thing to learn we all started mono faction it won't last it never does so prepare your wallet.
Sounds like an X, Y, K would all set you up well if you are wanting to stay rebel orientated. At 50 dollars the ghost gets you another small and large bases ship that might be to your style.
Also not everyone one started mono faction... I have always bought at least 1 of everything, if not more...
Don't forget the Epics. The Rebel Transport has a collection of astromechs and X-Wing pilots. I'd also suggest a Y-Wing and HWK-290.
And also look at the Starviper. 
(for autothrusters)
Most Wanted is a good way to get Z & Y minis and Y-Wing upgrades - make sure you get at least one of each of the Rebel Z-95 and Y-Wing tho.
Just buy whatever you like the look of.
100 point builds of every rebel ship..
Most Wanted, Rebel Transport, Y & K, and Starviper.
I just bought in a week ago, and so far i have TFA, Original Core sets, a T70 expansion, a yt2400/1300, A/B wing expansion and the Rebel Aces pack. What do I buy next or should I buy next? I'm exclusively a rebel player if you couldn't tell lol. Thanks in advance!
Maybe a starviper for autothrusters on your T-70s.
A K-Wing for having a K-Wing and TLTs.
Or more A-Wings and 3 scouts for a proton rocket alpha strike party with guidance chips? Maybe just start with the A-Wings.
Or Headhunters and most wanted for a Z-95 alpha strike swarm. though than you want again a few scouts *g*
At this points you have most of the essentials for rebels and you should buy around what you want to play really. Play around in a list builder and decide what list you would like to play and what upgrades you need to buy for them.
do not stick with just one faction.. you will be missing out on many good upgrades.. buy a little of everything.. and no I'm not kidding. one faction limits you too much.
Y-wing and K-wing is my call.
K-wing comes with two TLT's, so one for the Y-wing as well. Nice
Good luck in just buying into one faction though
Oh I totally forgot about the ghost. Yeah, get that ghost and a k-wing. A 100 Point ghost with phantom and TLTs should be fun 
I do intend to buy into another faction since my friend is playing either empire or scum so I might be buying extra models off him or even taking extra upgrade cards. And how does the Most wanted wanted pack help I thought it was only scum??
Was thinking of getting a Kwing just for TLT heard its a really good card
Some people will drop kick you to the face when you bring 4 of them in a scum build lol. It opens a lot of doors the TLT
The nature of the expation packs is that the upgrade cards are generally usable by all party's, (unless otherwise stated) so its still good to get everything for all the upgrades. The most wanted specifically has some great y wing upgrades, and as long as your oppenent doesn't mind you using a dial with the wrong art, it will also give you another y wing and 2more z95s to use in lists. (You will still need to get the rebel ones first though)
The nature of the expation packs is that the upgrade cards are generally usable by all party's, (unless otherwise stated) so its still good to get everything for all the upgrades. The most wanted specifically has some great y wing upgrades, and as long as your oppenent doesn't mind you using a dial with the wrong art, it will also give you another y wing and 2more z95s to use in lists. (You will still need to get the rebel ones first though)
Having never played in a tournament, Do you need the exact dials? IE a scum Y and a rebel Y have the exact same dials.
Im going to list the expansions you don't have and the notable cards it comes with (since upgrades are almost as valuable as the ships).
X-Wing - mostly for Wedge, no super notable upgrade cards I can think of
Y-Wing - for the ship mostly, but ion turret can be nice
K-Wing - Conner net, TLT, extra munitions and the ship itself
E-Wing - Corran, plus it's the only rebel pack with advanced sensors
HWK - recon specialist, plus they can be great support ships and now with TLT you won't give up too much firepower
Z-95 - um...ships to make a swarm? Wingman can be neat, but with guidance chips in the wild, munitions fail safe is a waste
Ghost - great ship, great crew, PREDATOR (although if you don't like the ship you can get 3 Khiraxz for the same price and get predator and crack shot)
That's all the rebel ships I believe. You can get MOST upgrades from staying mono-faction, and the past has proven that if you wait long enough, most upgrades will be available in-faction eventually. That being said, the following packs may be worthwhile:
Most Wanted - y-wing support mostly (title and bomb loadout) plus it gives you a chance to branch out into S&V faction
StarViper - autothrusters
Khiraxz - cheaper than ghost for predator, and if you get most wanted it's more usable than a Defender. Also crack shot
Rebel Transport - some really good X-wing pilots and some GREAT astromechs. If you don't play epic, the question of price is one only you can answer
Tantive IV - if you don't play epic, don't buy this ship. This was before FFG really saw the upside of using epic ships to "fix" existing ships (like the raider and the tie advanced), so it only has 4 cards (I think) that you can actually use in non-epic games, and only two of them are really good (threepio and artoo). Now that threepio has been a prize card, it's easy enough to find him online without shelling out the cash for this ship. That's a huge upside, since once you get into competitive play, many would argue that the raider is almost required for the imperials (advanced fix and Palpatine).
So, for the TL;DR, you can go a few different routes. You can build a list in an online list builder, the two major ones tell you what expansion(s) the upgrades come in, so you can build a shopping list that way. Alternatively just buy the ships you like as you are playing and learning, and branch out from there. My strategy turned into 1 of every ship, and expand from there. Generally I ended up with 1 of each large ship, and anywhere from 2 (E-Wings) to 5 (A-Wings) of every small ship.
A bit of advice though. As you buy more, don't do the math on how much you spent.