Well first of all, what you're describing is more of a power amplifier than a power supply.
Depends specifically on the waveform you want to produce. Using a step-up transformer on the output certainly makes the design much simpler, but puts restrictions on the waveform shape (must be AC-coupled).
If the waveform just needs to be a quick transition between two voltage levels, and you don't need to control the edges of the waveform very precisely, you could probably just use hard-switching semiconductors instead of an analog amplifier circuit.