Monocotyledonous plants are rather small group of plants compare to genetically diverse dicotyledons, so, the comparison  of evolution progress must be narrowed. Anyway, monocots have more genes moved from chloroplast to nucleolus resulting smaller chloroplast genome  with better controlled photosynthesis.  Adding C4 mechanism, average monocot is better adaptable to diverse and harsh environment comparing to average dicot. This is why mpnocots are considered more advanced than the dicots.