Slowly revealing new buttons is probably not a good idea, since UIs that change on their own are confusing; things are never the way you expect them to be.

Similarly, searching doesn't work well for beginners, because they don't know what to search for. If you only know what you want the result to be, and not how to get there, or what features you need to achieve the desired result, it's easier if you can just click on things you see, and undo changes if they're going in the wrong direction.

Microsoft tried pretty much everything they could think of in Word, attempting to do exactly what you're suggesting: make an app that works for professionals, but is discoverable for beginners. This is where things like Clippy came from. It's really, really hard to get this right.