Design first the propulsion system, top to bottom. When you are
convinced the system design is optimum for your application, THEN and
only then consider the optimum way to test the parameters of critical
interest. Compared to propulsion system design, the test stand is
almost trivial. Can only create the right stand when the system to be
tested is well known and understood. Perhaps have two teams: one
focused on propulsion system, the other on the correct stand to match
that system.
Edward