An extensive laboratory study was conducted using the dynamic shear rheometer (DSR) on an unmodified base bitumen (PEN grade 50/70) and several modified variants thereof. The base bitumen was modified with rubber particles and plastic waste particles. A DSR testing campaign was conducted on each material, consisting of thermos-rheological tests (temperature-frequency sweeps) and performance-oriented tests (multiple stress creep recovery tests, fatigue tests and low-temperature stress development tests). Some of the materials were also characterized under different aging conditions (short-term and long-term aging) to investigate the effect of modification on bitumen aging. The test results were summarized into a performance diagram, which is a graphical representation of some key values used to identify the effects of modification based on performance criteria. With the aid of the performance diagrams, it was possible to quantify the performance improvement of the bitumen resulting from the modifier. It was also concluded that the type of modifier has a great impact on the degree of bitumen modification.