Watch out with the UI. So many programs are abysmal in that regard, so it pays to be careful. The worst offender I've seen is 3ds Max, so you could use that as a negative example. A simple UI is especially important for the less computer literate, as many beginning bassists are. Get some people with little or no knowledge to test for you. There's an article on UI design up at
UserInstinct.com. It's worth a read, since nothing turns me off a piece of software like a bad interface.
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