Unmanaged rhymes with:
micromanaged, mismanaged, micromanaged, mismanaged, micromanaged, mismanaged, acknowledged, advantaged, disadvantaged, disparaged, encouraged, envisaged, hemorrhaged, leveraged, micromanaged, mismanaged, mortgaged, overleveraged, packaged, pillaged, presaged, ravaged, repackaged, rummaged, salvaged, savaged, underpriviledged, unleveraged
Unmanaged sounds like:
umscheid, umstead, unangst, unannounced, unassisted, unchecked, uncoat, uncoated, uncouth, unctad, uncut, unhinged, unionist, unionized, unissued, unjust, unmasked, unmixed, unquote, unsaid, unscathed, unseat, unseated, unset, unstated, unsteady, unsuited, unswayed, unused, unwashed