This one is clearly a challenging project. There's a lot going on with that handle, to be sure.
Regarding the nut that holds it all together, I think the angle of the tail end of the pommel is part of what makes this difficult. That angle would work well on a glue up pommel, but because you need to put a nut there it becomes really hard to get something in the hole that restores the flowing line you have outside the hole. So maybe the answer is not to try to restore the flowing line, but acknowledge it is intentionally different. On the Inquisitor you put a lanyard ring at the end. Maybe something like that would work again... or some other protrusion in the rear that looks intentional. Just thinking out loud here... I don't really have what feels like a good idea.
One other thing, you now have several textures in the metal work behind the blade, and there is a certain lack of cohesion manifesting itself. Maybe you can do something with the nut that ties in with the dimpled texture of the finger guard. Or maybe you could apply that texture to part or all of the pommel.
Again, no solid ideas here, just random thoughts.