Bingo!
The post-credits scene changed everything for me. A character evolution that is easily justified by surviving what he went through in the Sarlacc.
To become the underworld boss, you can't do it alone; it's not like bounty hunting where you can survive by watching your own back. Fennec problem solved.
He'd also need a broader and fuller understanding of what kind of authority will be trying to crack down on him. Following Mando into Imperial infiltration problem solved.
Taking the throne solves all my previous issues.
And get this, Khev: my issues I had with Maul being the crime boss post-OT in GL's treatment are gone with Fett. No Sith stuff. Just underworld being, um... "underworldy."
They can even have that premise play out now with Fett in place of Maul if they want to bring life to that aspect of GL's post-OT ideas. Amazing potential, imo. So much good came out of just five minutes. I'm floored.