Advice where to go (F2P)

Buy Ships ONLY in the GW Storefor now.

First farm ONLY the Geonosian ships. You're pretty behind on them.
Then farm ONLY the rare ships - Clone Sergeant's ARC-170, Resistance X-Wing, & the Imperial TIE Fighter.
Farm all 3 of those at the same time, since they're rare & otherwise you won't be able to spend your 1200 currency per day.

If they're rare enough you're still not able to spend your 1200 currency all at once, then make sure you keep 3,000 tokens in the bank so you can buy the rare ones every time they show up & spend excess on the more common ships. Any ship is fine. You want to collect them all.

Once you've got all or nearly all the ships done, you'll either want to spend on characters in that store again -- you'll need Cad Bane, Phasma, & Magmatrooper for sure. K2SO, Resistance Pilot, Dathcha, & Tusken Raider as well.

Remember, don't buy any of them before your ships are done, but once they are, maybe this order
GW Characters:
1. Cad Bane
2. Magmatrooper
3. K2SO
4. Phasma
5. Resistance Pilot
6. Dathcha
7. Tusken Raider

As for the Fleet Arena Store... don't get the Geo characters from there. That's too precious a currency. I also wouldn't buy zeta mats there yet. You want to get all the exclusives that you can only get there - Vader, Grievous, Rex's ARC-170, Ahsoka Fulcrum & Chirrut. There's another ship there that's also exclusive to the Fleet Store (or nearly so).

But Geos have a good source elsewhere. You shouldn't buy things with a good alternative source from the Fleet store. GET Store & Fleet store have very specific things you can only get there (or are very, very hard to get anywhere else).

GET Store should be Hermit Yoda for GET 1 & Malevolence for GET-2. That's it. You shouldn't stray from those until they are done.

Cantina store is interesting given your roster. You probably don't want to buy HR Scout since it will come free when you farm General Hux (he's on the same node). You've got Ahsoka & Chopper.

Cassian's U-Wing, Pao, Bistan, Jawa Scavenger, Fives, Stormtrooper, FOO, Poe & QGJ are the ones you need.

I guess my recommended order would be...

Cantina Battles Store:
FIRST - NO BUYING ANYTHING UNTIL SHARD DROPS DOUBLE. Then:
1. Stormtrooper => 6*
2. FOO => 6*
3. QGJ => 7*
4. Fives => 7*
5. Poe => 7*
5. Bistan => 6*
6. Jawa Scavenger => 6*
7. Cassian's U-Wing => 7*
8. Pao => 6*

Now, some of those 6* toons will complete themselves with event & GW shard drops. But others won't. However, if you have them at 6*, when you finally decide that you want to focus on their ship or faction or an event where they're required, you can go back & finish that up quickly. Farming shards can take a lot longer than gear. You can gear a toon from g1 to g12 in 2-3 weeks, and get them to relic 3 in 2 more weeks, for 4-5 weeks total from nothing to relic3. Farming shards usually takes a lot longer than that.

There's also nothing you're going to want to buy here OTHER than shards, so just get all the toons farmed up to 6 or 7 stars, then go back to purchasing Cassian's U-Wing's Blueprints & turn them into Shard Shop currency.

That said, none of these toons are a real priority for what you're doing. So you could do them in a different order if you wanted. It's not like there's a clear advantage one way or another.