GAS? oh, no.

I'm not as bad as I used to be.

There are two things that I do before I buy anything:
First I ask myself, "Am I going to use that gear in the long run on a daily basis?"
Second: I wait for at least 3 days.
Usually after 3 days my "GAS" diminishes... plus by than I find something else to yearn for
I'm barely scratching the surface with my BK-9, that's why I don't want another arranger.
And with the DAW, I'm learning something new every day. I bought another book the other day, called "The MIDI Manual", it was like $6 on e-bay.
By the way, have you listened to my SMF that I created with the BK-9 and the Cakewalk?
It's a song from Bach called Arioso.
I used something simple. Bass and drums were recorded inside the BK-9 (with the arranger) than transferred to the DAW and the other tracks were recorded all at the same time, with the BK-9 as the controller.
My setup is simple. Computer + BK-9 + a Shure SM58 are connected to a Yamaha MG10XU mixer which in turn is connected to two Roland KC-60's. If I want to record Vocals I use the Roland UA-22 connected to the computer.
I also have a Sony MDR-7506 monitor headphone connected to the Yamaha Mixer.
I like one keyboard setups. I know some folks like to have two keys, especially a digital piano as a second one. But I got used to having only one keyboard. This is from the old days when I was carrying my Roland D-10 to rehearsals on buses and trams.