Like the gamepad support lastly added (wishing more controls over the activation options for that though), a mouse support following the aim mechanism of the head-aiming with gamepad, but with the difference of the origin point of the line :

taking the head position variables at the recenter/reset moment, and discarding the head's inclinations, the mouse moves the target point of the line on a the sphere surface with the center of origin matching the head's one . The trick would be disabling the mouse aiming as the line targets the dash's desktop screenspace when activated. (colision detection possibly avoided with boundaries for less costs in ressources? but really helpfull for the user, therefore with an option to activate it or not, like the one we'd wish for the gamepad support :-p)
Simple and efficient.

Hope I'll be read. Thx for your attention.

Having read the rights of the account holder, if my idea is retained, maybe should I have some kind of rewards ?
:-p
:-)

^.^