Run test alone for a few cycles (3). If you continue to see quality results, keep it simple. Adding more compounds increases the complexity of managing side effects and if test alone provides results, "if it ain't broke, don't fix it".
Asking what compounds come next is like asking how long a piece of string should be. It depends on your goals and objectives. Some guys add orals, others stack injectibles, but it all comes down to what you are trying to achieve.
Many of us who have done this for a long time have learned that more is not better.