Since my strongest characters are all part of the Phoenix squad, should I grab Ghost from the fleet arena store as my next ship? The IG-2000 piloted by IG-88 also seems like a reasonable choice since the droid is also a bounty hunter.
About these questions specifically: Ghost is very important for any early light-side team. IG-2000 is a lousy ship for a long time, but it's absolutely necessary for the Millennium Falcon and it's never too soon to work on it. Don't upgrade IG-88 past gear 10 unless you decide you've got a really good reason to do so (but you'll be level 80+ before that even becomes possible).
Remember that in the very, very earliest days of fleet, no one has good synergies yet, but some people will get them, soon, and they'll be the people you'll be competing with for the top 5 in fleet. Grabbing random ships just because you already have gear on the pilots can get you into the top 200 and maybe even 100, but it won't get you a crystal income. Only good synergy can do that, and the Geonosians are the easiest high-synergy team to farm.
So Phoenix because you need them long term, IG-2000 for shot term needs if you have no better option, but also because around level 80 or so you'll want a mid-grade IG-2000 for the MilFalc event. This means it's never too early to start grabbing available blueprints, but it IS probably too early to use your precious upgrade materials on that ship.
This may sound confusing, but IG-2000 is best farmed for blueprints, because that takes a long time, but left at level 1 until higher priority ships are finished and/or you're getting really close to being ready for the MilFalc event.
Always remember that leveling, upgrading, and even gearing is easier and quicker than farming shards or blueprints, so farming a lot of things to 7*/level 1 isn't a bad strategy. It allows those toons or ships to be available for your credits and gear and ability mats the moment you have them to spare, instead of realizing you're getting close to ready for an event but then discovering that farming the shards/blueprints is going to take 3 or 4 months.
I've been there. It's terrible. Don't sacrifice Geos or Vader or Phoenix progress for IG-2000, but grab whatever shards & blueprints you can for IG-2000 and other ships that aren't your top priorities (Anakin, the Bounty Hunters, Ahsoka, the Clones, etc.) whenever you can. It makes preparing for events or switching to a new meta much more painless later when you have the ships fully unlocked and are just waiting on pilot gear or cash.
