Once it's finished indexing things it feels darn instant to me. What hardware do you use? Also which programming language? I've used IntelliJ with Java, Scala, Kotlin, Groovy, Markdown, and many file types and it's really snappy.
I have an i7 6900k and 64 GB of ram. Indexing on the project I work on takes something like 3 hours. But I'm not even talking about that - just the basic user interaction, opening a menu, switching tabs... It's notslow but it drags its feet a bit.
