I would also like to vote for suggestion #3 (designating controller buttons as modifiers). Ideally, I would like to be able to set at least 2 buttons as modifiers, and to be able to combine them (e.g. L1 and R1 (left and right triggers on the controller) are set as modifier keys, X button on controller maps to one key, X+L1 maps to another key, X+R1 maps to a third key and X+L1+R1 maps to a fourth key).