Bachus, keep in mind that you are a very talented and rare individual, a one in a million kind of person. consequently, because of your wonderful abilities and their rarity among arranger keyboard players, it would be very unlikely that any manufacturer would design an arranger/workstation around your needs. Consequently, in situations such as yours, you will likely have to go the software route and either design your own programs, or find someone who has already designed this type of software to fit your technological constraints. Like most retail products, arranger keyboards are pretty much designed for the masses - not individuals. That's what keeps them in business, just like any other product being sold to a general market.

Good luck,

Gary