The next thing to review in the configuration is where your program code is located. IBM recommends that you install as much of the WebSphere for z/OS code in LPA as is reasonable, and the remainder in the linklist. This ensures that you have eliminated any unnecessary steplibs which can adversely affect performance. If you must use STEPLIBs, verify that any STEPLIB DDs in the controller and servant procs do not point to any unnecessary libraries. Refer to UNIX System Services (USS) tuning tips for z/OS for USS shared file system tuning considerations.
If you choose to not put most of the runtime in LPA, you may find that your processor storage gets a bigger workout as the load increases. At a minimum, WebSphere for z/OS will start three address spaces, so that any code that is not shared will load three copies rather than one. As the load increases, many more servants may start and will contribute additional load on processor storage.
Review the PATH statement to ensure that only required programs are in the PATH and that the order of the PATH places frequently-referenced programs in the front.