As far as making beats goes, at least in my experience, practice doesn't really feel like practice..... It's more like a hindsight kind of thing. A lot of the time I'm not even aware that I've improved until it becomes apparent a few months later when I look back and realize that I sucked lol. Maybe that's because every track I put out is made with an actual purpose. I'll never make a beat only for the purpose of becoming better at beat making, but I know I'll get better either way.
In my mind learning to play the keys or something like that would feel more like a process of practice, because it's something I'd repeatedly do solely for the sake of becoming more sufficient for when I'd want to add live keys to a beat or something like that
But a little more on topic...... I agree with Bandcoach and mobeatz's posts. There's still a pretty large amount of trial/error involved in turning my ideas into audible form. Someone much more polished could probably do what usually takes me days in a few hours