SLKR provides a counter to normal Executors so you can spare Profundity for Leviathan. EST. 4 months.
Rey is the better GL with a worse Fleet that can clean up things and better requirements. EST. 4+ months (Raddus).
LV is much better than SLKR, better than Rey, but more expensive than both. EST 4-5 months.
Leviathan is a defensive monster but would take at least 4-5 months.
Dr. Aphra is great on Attack to beat Jabba, Trench, Zorii, Tuskens, Dash and all these tedious teams you encounter. EST 2-3 months.
JKCK is good for your Jedi collection and a good stabilisation project (not that you need one 😅). EST 3 months.
I would honestly wait for Leia's kit and the rewards in Endor Escalation (Mythic Tier) before deciding. You're really close to her, just need to farm the Marquees (which will be the major holdup) but I can see you getting her 3 months after Drogan becomes farmable.