The major light improvement in P8 is the introduction of Global Illumination, or IDL, as a standard package.  It thoroughly replaces the need for IBL, although some individuals have managed to intergrate both IBL and IDL together with satisfactory results.  A big factor, you can use ambient glow to effectively and correctly illuminate a scene without the benefit of external lights.  Yes, you would need to invest some time relearning the new process, but it will take no time at all and well worth the effort.