i have a couple of suggestions, If you are going to use the arrow keys, then try using numpad zero for jump, then you shouldnt have to move your hand.
Also try remapping some of those keys that are close to your left hand, maybe the page down ones etc.
and finally if you can afford it, get a naga mouse. at the very least if you can use all the keybinds on there you can set your interrupt under your thumb for easy use. Interrupt must be on a easy keybind