Fran wrote..."When I play arranger keyboard today, I usually turn off arranger and play trio type stuff (left hand bass, piano, drums.).
Sometimes I will add the auto bass, and/or guitar part of a style.
In my opinion... there is emptiness"
To me that sounds like
emptiness 
...what is the sense of playing an arranger KB if you shut off most of it's parts?..
What type of music scenario room is being played with just bass,drums, piano, alone ?....
lounge, restaurant, cocktail hour,?.....
what happens when people want to dance, or hear more pop uptempo tunes with vocals, etc, etc,..?
And how does the younger generation in today's music atmosphere embrace LH bass...?