A friend borrowed my wheel but, with 'great skill' managed to break the metal trolley handle.
I copied the original design and printed it using TPU 95a instead of PLA so it will withstand more impact - just in case!
I made another one with the slope of the handle going the other way. I find that it's easier to hold onto and is less likely to catch on rocks etc.

NOTE - I like the feel of the TPU and the fact that it is unlikely to break on impact....... But....... Because the attachment to the trolley handle supports is fairly narrow there is some 'play' when you are moving the wheel around.
I'm trying to think of a way to 'stiffen' this area. I did think of inserting metal rods up the handle support area but you'd have to drill through these to be able to attach. Another thought was to print the support area out of TPU and insert that.
Maybe, make it in two halves with a 'core' of TPU. Not difficult to design, just a pain to make.
Any suggestions are welcome!

Other

Ender 3D Max

No

Yes

0.8mm Nozzle

30%

This can be printed using a different sized nozzle. I chose to use a 0.8 to speed the process up. It took seven hours to print.
I used a gyroid 30% infill with five wall thickness to give it a bit of stiffness.

You could use any filament eg PLA but I used some eSun TPU 95a

TPU 95a sands quite well.
I did this to remove some of the layer marks.
After that I went over it with a hot air gun to remove some of the 'hairyness' that the sanding left.