The atmospheric absorption produced by liquid droplets of clouds does not appear in your figure, WaspAir, Isn't it? To calculate the equilibrium temperature without involving the fundamental parameter related to the formation of these droplets (dust, catalysts, cosmic particles, solar winds, etc.) is like calculating the internal temperature of an humain according to the quantity of its fooding and the thickness of his clothes.
And not only clouds are not taken into account here, but I do not see the nitrogen in the image either. Is it not 78% of atmospheric gas?