Jos, I agree with your assessment of hardware vs software based arranger systems. I selected the software route based on the following considerations:

I like very high quality lead or melody voices.
I like to set up the system to suit my needs.

Yes, it takes some know-how to get this all to work. Keep in mind that I am considered a morron and still, with effort, I was able to get all things to work. I guess I embarked on this journey in part as a challenge.

I will also say that once you go down the software path, make the appropriate investments (time & money) you will never look back.

Furthermore, I believe the future is software based but prices have to come down and the technology needs to be user friendly.