Your account is well underway but it is obvious that you lack training credits and droids. your idea is correct, the arena team you’re planning is correct, but that’s not the point. You need a team of scoundrels to close credit events and droids at grade 4.
Problem number two of your account is lack of focus on ships, especially those on the dark side
Close the 7-star Darth Vader by purchasing fragments from the ship shop.
I don't know what you are doing on yellow energy (but reserve 200 a day for Bossk and (Hounds + jango)
Complete the Boba Fet in the Guild coin shop
Cad on the GW 7 star, then geonosian ships then go to the rebel ships, and then the republic ships after completing this close the other toons.
In the Canteen, stop what you're doing to go after Mission and T3 and complete Tie Silencer and Kylo unmasked first. As soon as you complete them, go back to farming whatever you want.