In plots, all axis numbering appears on the left by default, while when using the AXIS2 parameter, the second axis on the right is used.
Is there a way to reverse this default behavior and have all axis numbering appear on the right by default and AXIS2 numbering appear on the left?

No, AXIS2 is always on the right.

Is it possible to request that feature to be added?
The time series runs from left to right, with most recent values on the far right. It would be very convenient to have the main axis labelled on the far right, next to the most interesting (recent) part of the plot.

Ok, I've added it to the list, but with low priority - after all, in most charts and histograms the main axis is usually on the left.