Well, slowly getting it to run (hope to finish till this weekend) and got a few questions. At the moment I got the enumerator and the binder running, able to attach basically whatever is in the DI-standard joystick structure. The actual control, response curves etc are ready as well, and I'm mostly cleaning the stuff up. Unlike the XInput support from the current build, the DInput will not be multiplexed, but will be additive instead (as, opposed to how a gamepad can be used to control a real-life drone, and can be used as a complete control device here therefore, a flightstick may lack the ability to do several things unless in conjunction with a keyboard). And, FIY, yes - the selected device can be registered for future use, where it will start automatically (not really portable tho I guess, as stores the device's GUID) - the layouts are portable however, as are stored in separate tiny files named after each device.
Now, for the questions. So far I made it select a single device (for which it loads the control map as well, which you can edit in-game) and run like that, e.g. the keyboard is always available, mouse available whenever the axis pair meant for the yaw and pitch is not bound completely (for an obvious reason), and discrete, axial and POV controls, should they overlap, will be properly combined (yes, you will be able to bind a button as, say, strafe left, an axis for horizontal strafe and a POV switch to both strafe and ascend/descend all at the same time, and any combination of those will be correctly parsed). Should I leave it like that, or do I have to (won't really take that long I guess) make a control stack as well, allowing to assign and use a few DI devices at once (in this case you'd have to assign devices like #0...#something, where the layout of device #1 overrides the one of #0 in case of a direct overlap - say, if both are bound as "axis X", the one from #1 will be used, but binding one to strafe_x, and the other to strafe_left button is still combined - and so on)?
Also, about the deadzones. Should I rely on the DI ones, or have an own dead-zoning in software instead (atm I only tried the latter, just like with XI)?