Great info
So do you think it's a geometry issue or a balance issue or some of both.

I would first make sure your rear cross over point is the same side to side. To help rule out balance issue. You did change the preloads.

I ran into this and found that I had the cross over (spring divider) in up side down on one side. Oops on my part.

Did you jack up the front and check the camber with wheels turned compared to straight. And then compare to ride hieght straight and wheels turned. Since it turns right good and if there's a difference I would use it as a setting for the left turn. I would also look at how much the ackerman is right to left turn to make sure your bump kit is square. This could have an effect on the camber when turning. If your frame is bent you may have to run a different setting side to side or change the steering pivot point lengths as well. If your arms are a little different on lengths side to side the bump kit pivot points may need adjustment to get the same ackerman angle.
Before you take it apart do a circle test at slow speed

You can feel and measure the difference. This would be for static setting testing caster to camber and Ackerman.
The you can adjust the camber to match in a turn condition and speed up things for a balance condition test. Leaving caster alone it will not upset the stability In a straight line unless you have excessive toe out. Then if you had a slow speed compression you can add stiffness by adding clicks or change cross over to add stiffness. Maybe add some gas pressure since you added bleed.

No doubt it will handle great when your done and add valuble info to the site for other.

What year of trx? I think meth used 06 and had posted some numbers for his setting maybe a good start.

Side note for others. Changing the caster has an effect on camber when the wheel is turned.
This also has an effect on body roll which changes the balance via tire loading. If only there was a guide to go by. Zero will be close to have one when he is done.

When I got this Dave-Co LT pilot, the front right upper ball joint was loose. After about 9 months of rides it was getting worse. Wheel was able to be moved 1/4" in the direction of negative caster. I was starting to fear separation and crashing at speed.

Why did the original fail? Some say they fail find when bound, but in the case of this machine it was not binding. I believe the massive welding heat from Dave-Co chopping off and welding the OEM joints to the long travel arms caused this joint to give way due to excessive welding heat. From then it was only a matter of time.

The new balljoint is from Alba Racing for a TRX450r. Its got about a 30 degree angled head.

Yes I did have to chop the arms off the OEM ball joint. I TIG-welded in a 16mm threaded sleeve to where the aftermarket ball joint would then thread in nicely. The bad about this is this likely won't work for a stock pilot as I also had to make several adjustments to the inner Heims (Which are fully adjustable on this LT pilot) in order to get caster/camber/toe back to exactly where it was and all is now tight as a virgin.

I hope this joint holds up else I'll be looking for some OEM TRX or FL400 arms to chop up...

Also I hope my lower ball joints live a long time. My fear is the weight, suspension, and ride is counting on the strength of the lower joints much more than the uppers. Will see.

Also worth noting, swapping out the FL front hubs for TRX450r hubs wasn't exactly easy. The geometry of the two hubs are quite different. If it weren't for all the LT adjustability it would not have been feasible. From camber, caster, toe, dumpster - everything had to be reset from scratch.

That being said, I believe the TRX450r hubs made a truly positive difference in machine braking and turning capabilities. Both L and R turns feel strong and now equal. Braking is immense. Swapped to stainless lines as you can see in the photo also.

I think you should be fine with those joints, only thing I suggest doing to pull the springs off the shocks and cycle the suspension thru full travel, you want to make sure the joint is not what is limiting travel.
I am using Rickey stater trx250r ball joints on my LT pilot those joints are straight and the angle is in the attachment, they work fine, but I do need to get a replacement now that you mention it
I am using Cannondale spindles and brakes on mine along with the Cannondale tie rods.

make a habit of checking ball joint prior to each trip and replace if needed.

Cool you got it worked out.
Any way you can cut off the lower at the arm and insert the 16 mm sleeve and weld in. It would move the lower out a little and make more room for the upper to have more adjustability.
Got love disk breaks and trx spindles.