First off, I'd like to say thank you for taking your time to read this; I would like to keep this post short and sweet.
The banker is very inefficient. As seen in the image below the banker is often invisible (due to the tree) while mining. Another thing I get frustrated with is how he moves, in order to do a skill that requires you to constantly open a bank you'd need to go somewhere else besides the dzone. Also clicking a moving guy while trying to grind is a pain. If he could be placed further towards the water and made so he doesn't move anywhere it would solve all of these problems.