I used to make a lot of my own styles, on the Technics and Yamahas.
All I needed was drums, bass line, guitar strum and piano rhythm. Now, it has become more and more time-consuming, because now you have 4 variations, several fills, severals intros and several endings. Also the factory styles and converted styles are better than they used to be and it is no longer necessary.
A few years ago, I had to make almost ALL the Country/Western styles I needed. In fact last year with the Korg PA80 I had to make a couple. There was no style available to play "Good-hearted Woman" or "Blue Eyes Cryin' In The Rain" - type songs. Everything was too busy, too hokey, or too "rock n' rolly". Hope it's o.k. if I make my my own adjectives.
DonM