My thoughts on arrangers are the complete reverse of yours, Russ.
My primary instrument is the arranger and I think of other instruments such as the Acoustic Piano and Hammond B-3 (and Fender Rhodes) as additions to the main body of work I do with the Tyros4.
The Tyros4, and my previous arrangers, have been veritable Swiss Army Knives and literally the basic instruments from which I work.
Many years ago, I might have looked at it the way you do, with the arranger the more "occasional" instrument, especially when I was doing a lot of band and recording work using the various keyboards I had in my kit back then.
I still think the best thing about having an arranger here at my apartment is being able to sit down and just play...and, play in any genre I wish, with as much background instrumentation as I choose...AND, at MY convenience, meaning the band is always up for a tune...even at 3:00 AM.

And yes, HAPPY HOLIDAYS to you and everyone else here on SZ...this is the time of year when that special event happened that made Christmas so very special to kids young and old alike...the birth of Santa Claus.

Ian