There is a world of difference between 'assembling' a style into a new one, and creating one from scratch. Not that there is anything wrong with doing that, and it's results can often sound quite unique. But the skill set to do it is totally different from style CREATION.
Let's face it - to make a style from scratch, to close to factory standards (what's the point of a style that is LESS, anyway?
), you need quite prodigious skills at emulating real instruments. Drums, and guitars, especially, are techniques that are alien to keyboard players, and it takes a LOT of study to create something that sounds like the real thing on both of these.
In fact, a lot of the best factory styles from the top manufacturers are created by a TEAM of players, often using MIDI drum kits and MIDI guitars in the hands of REAL players. This is why, I think, that you don't see the manufacturers releasing a whole lot of new styles in between model changes. They have got to be fairly expensive to produce, and the manufacturers know that the minute they sell one, we trade them around like bubblegum cards. So, very little chance of recouping the cost.
I sometimes wish that the manufacturers could use some kind of copy-protection (maybe tied to the hardware, which can't be cracked) for factory styles, then they would get a guaranteed income from EVERYONE who use the style, rather than just from the first person who buys it, and then shares it with all his friends. I know, on the one hand, this would make sharing it harder, but on the other hand, it would encourage the manufacturers to continue style development using these incredibly gifted teams of players in between model releases.
Certainly, I tend to feel that the best, most dynamic, exciting styles have always come from the factory, and user 'created' styles (from scratch) never quite get there. So anything that encourages them to continue churning out these killer styles, even if it involves some inconvenience to us all might be a good thing.
Naturally, this copy-protection would apply ONLY to these new styles, but we have GOT to find a way to somehow allow them to make some profit off new styles, or we end up with what we have now... Basically, NOTHING much new from the factory until a new model comes out (and then it might not work with the older model).
That's FAR too long a wait for high quality styles, if you ask me...!