It also had bass and treble controls that provided an EQ for the effect. You could also take inputs from multiple sources (mic, instrument) and a mixer, all easily accessible from the front panel. Roland had the foresight to design something that was meant to be played and interacted with. They didn’t just see this as a tape delay with a wet/dry knob, they saw the potential this had to help creative people articulate the music they heard in their head.
If you think through what music your listener was likely exposed to as a child, you can easily figure out how to write to job their nostalgia response. But it’s important to remember that “nostalgia” can also be associated equally with sentiments of sadness and loneliness as it can joy and comfort. As a composer, this is where it becomes important to play with instrumentation, timbre, and tempo, in order to get the right balance.