Would the benign spiral maneuver be one alternative to dealing with being "stuck above" or inside a cloud?
It works in most gliders because they tend to be neutrally stable in roll and - the big one - have speed limiting spoilers/dive brakes.  I'm not sure it's safe to do that in an older glider without speed limiting spoilers.

In any case, most power planes, once disturbed beyond the ability of dihedral effect to restore level flight, will naturally descend in an ever steepening spiral without pilot input.  There aren't any ways to limit the speed on a GA power plane (gear and flaps won't cut it) the way spoilers/dive brakes on a glider can.  It would need a speed brake that can hold the plane to below Vne in a vertical dive.