The big thing here is that cabs have a big impact ( for me the biggest) and cool cabs make muuuuch profiles muuuuch better.
As in real life !
The impact of a (real) cab to a (real) amp is huge and comparable to the influence of the pickups to the sound of a guitar.
My experiences during my "tweaking-years" with real amps is the following impact-order-list:
1. Cab
2. Speaker
3. Capacitors of the tone stack
4. Preamp Tubes
5. Phase Inverter
6. Power Amp Tubes
Though the specific impact of each component is not completely comparable and concernes different aspects/components of the overall-sound / amp-behavior