Any musician (including vocalist), should be able to play with an arranger. Being able to keep in time is just one of the basic things of playing that you can not get away from whether playing an arranger or not.
I could remember when I use to play in a band in the 90s where we use a drum machine for percussions. There was a drummer, bass player keys and a guitar.
Playing an arranger keyboard in a band there are two ways you can do it. You can play just as if you were playing a keyboard with out arranger features or you can use some of the arranger features.
I have used my arranger for drums and percussions when there was know drummer in the band. Everyone played as if the drummer was there and there was not any major differences except you miss the energy that a live drummer brings to the table.
Weather I am playing with a band or by my self or a duo, I always try to create my styles as if it were a band. I don�t use all the tracks at one time and I have 2 drum tracks one for bass and snare and the other for percussions.
I strongly recommend style creation and modification so that the style can fit your playing. This way, you don�t have to wait for a keyboard manufacture to create styles that may not fit your playing style.
My humble opinion is that I am in the music business and I am willing to make the sacrifice to sound as good as I can on a gig. That includes among other things practicing, buying the right equipment and style creation to name a few. Yes it takes some time. But once you get the hang of it and you have a number of them, it is not that daunting.
I have about 20 core styles that I use on gigs and the songs rotate between those styles.
Just my opinion
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TTG