There is a problematic horizontal change of direction in this drainage pipe. It is connected to a sanitary tee, but the flow of water is directed right into the cleanout cap instead of the 45 degree elbow. Obviously this leads to constant clogging issues. Would I be able to remove this sanitary tee and rotate it? (Flip it over horizontally and then a 90 degree counterclockwise turn?) So the flow of water is directed into the elbow? Or are there bigger issues here? Thanks in advance!
Replace the cleanout with an elbow. Since you have a lot of room, put a wide sweep elbow.
Your cleanout should be at the OTHER end of the long run. Since you're already cutting in to the drain pipes, do it now. If you wait for a clog to install a cleanout, then when you cut the pipe you will have to deal with the contents of the pipe. If you install the cleanout now, the pipe will be empty.