Don't save for packs. Best prices for new characters is shipments (outside of farmable toons). Every character is released on a cadence now. You unlock them at 3* or 4* in an event, and they are released into shipments after a few weeks (usually a month and a half later). Another few weeks and they are given a farmable location. Rex leads are still meta. I would gear up a Rex if I were you. It's one of the fastest farms. He is farmable in ship shipments. Ships are huge. You will need to build up a team of 8 non capital ships 5* minimum. 5 of them should be darkside for unlocking the Executrix (so you can farm zetas). Start down this path and you should catch up pretty quick.
If you want to start over, pick up a rebel/scoundrel team. Palpatine event is on a two month rotation with yoda event. Credit heist is about every two weeks. Pick up Lando(L), Biggs, STHan, Boba, and Ackbar. After that you can grab IG88, Cad Bane, and Wedge for full rebel team (competitive arena and Palp event) and a scoundrel team (credit heist). Good luck.
