I don't see this as an option available currently, so I apologise if this is already implemented (if so, where?): the ability to trigger one motor, the other (or both) to a user specified extent, when applying a given input.
For example, I could set O to trigger the large motor X% while I have it held down.
In particular though, this thought was triggered by playing a flying type of game, while using motion controls to assist with some handling of the craft. I was having difficulty feeling the, for want of a better term - clutch point - when transitioning between off-level and level. Having the ability to get more feedback would be absolutely wonderful.
Allowing users to add rumble to inputs, and to set up a strength curve for rumble when tied to axis controls, would be great.
P.S. As a suggestion, I think the offset range for Gyro Z could definitely be expanded. At -100, what IM thinks is level is really only the slightest of dips forward. A setting of 0 actually has my controller tilted back. I understand there are likely differences in calibration between individual controllers, but that in conjunction with expanding the ability to use motion controls are reasons enough to accept a very wide range for user settings. For example, my natural means of holding a controller is to have it tilted forward; so I would be far more comfortable having a much lower 0 for pitch control.
I intend to open the rumble motors up to macro capabilities, I also am thinking about adding a "shift" functionality to the tuning capabilities of all axes, the term offset already being reserved for the adjustment that shifts or rotates what sticks consider top dead center.