I'm so used to using VoiceAttack for some basic commands that I find it not just less of an experience but actively frustrating if I don't use it.
Initially I had a very complex setup with scores of commands, and complex strings of commands to control stuff that is only accessible through the side panels. However as I've become more skilled with the controls over the last 9 months I've stopped using a lot of them and now I just have about 20 commands, but I use them constantly.
Transferring power in battle with VoiceAttack is worth the price of the app alone - it means you can focus on weapon selection, aiming and combat while transferring power with a word as required. Other very useful commands are landing gear and cargo scoop deployment, screenshot capture, silent running toggle, flight assist toggle, and re-centering TrackIR.
All these can be bound to HOTAS buttons, of course, but if you have the Thrustmaster Flight-X (which I do) its button bindings are limited. However even if I had a more up-market system I'd still use VA for those commands.
Beyond the absolutely essential commands you can then get into more complex strings. These work just as well but my experience has been that I forget to use them sometimes and just use manual controls as it is faster and more dependable, whereas the essential controls become second nature.
Beyond that there are the "vanity" level controls like playing sound clips, voice responses, music etc. None of these are necessary, but you can have heaps of fun with them and really customize your ship, if you like to do that sort of thing. I did once have sound bites for responses on all the controls, but it became tiresome. The only ones I still use are sound FX for the landing gear lowering and raising, and the cargo scoop deploying and closing. I made these back before there was HUD indication for the status of those systems, but I still use them as they give me a useful audio confirmation of the command. There is, of course, an in-game sound for landing gear, but it is very soft.
https://www.youtube.com/watch?v=q8Kk5V-HDyM&list=UUcVoNK3Fo09gKLlAT434usQ