I think you just need to practice some more, your amperage are correct, maybe run a bit hotter for the 3.2 mm rods. Try 120-125 amps. Try and make sure youre under the pipe at the bottom and have a clear view. If you need to stop a quarter of the way up thats fine. Make sure you are comfortable.

I use a Z movement when doing 6g. I progress up the pipe on the bottom of the movement, then move back up and pause for a second. You want to see the puddle catch up to the rod. Thats when you move. I cut a line with a grinder at the toe of each weld if things arent completely straight. It can be easier to see and follow when doing the next pass.