Apart from the possible greater mass & speed, flying a light twin with both engines operating is not much different from flying a retractable & CSU single.
The catch is that light twins are *especially* deadly if an engine fails AND you're not up to speed with the handling & performance problems. Statistics published by Oz's CASA some years ago showed that, while light twins are involved in fewer forced landings/crashes due to engine failure than singles, those that do crash have a much higher fatality rate.
That means some amount of regular assymetric practice to maintain competancy is needed. The less the experience of the pilot then the shorter the duration before significant skill degradation occurs. Even more so if considering IMC flight.