I would do
ISD and Gladiator are first ships you want. They will be your primary damage dealers ship wise
Follow up with squadron packs for each. (Squad 2 is pretty good compared to Rebels version.)
After that you want a Gozanti for support and Quasar for upgrades to buff your Victory and a good squad pusher.
Raider for a good picket ship against squadrons and another Gozanti.
That is what I recommend starting out. Your gonna want to pick up the Victory for cards eventually as well.