In UK most courses I have seen dont do SEIR and MEIR, normally you just do MEIR, and that is all you need.
You do the CPL in the SE, because it is cheaper, and with your MEIR your rating covers all you need to have.
Just CPL - SE, ME & MEIR that's all.
If you want to spend more money you can do your CPL in ME, but there is no need for that, as all will be covered in your ME IR and your ME rating.