I am just thinking the pole would give you much more vertical drop so the arm can get maximum horizontal reach.
Remember with a setup like this you will need to have a secured return position for travel that takes all stress off the arm.
Also regarding the monitor,if yours is a little older this may be a good time to look at newer models which can be so light
it is crazy.
Lighter is better as long as its a decent monitor and these days a 24" monitor can be $100.00.