While you are taking 381, many people would suggest not taking any additional EECS courses, and maybe not even any additional STEM courses at all. You may try to take some of your intellectual breadth and/or general elective courses, but as a transfer student, you may have already had all of those credits taken care of?
I’m sure 270 helps provide some helpful background for 370, but anybody can guarantee you that 203 is absolutely sufficient.