Guys, I think we have all missed a critical element here. For me, the choice of equipment is shaped by the intended final product.
If you want to sound like a 10 piece band, you "ain't" gonna get there with just a piano. If you are playing where dancing is a part of the deal an arranger gets you mostly there, with some significant limitations/compromises.
If you are an entertainer doing show material as a single, the arranger may be the way to go if you don't want to do karaoke
or use tracks in some other way.
Use equipment, but don't become dependent on it, I say. Decide what satisfies your need to play, and DO IT!
I am cutting back, and a local restaurant wants me 2 hours Thursday and 4 hours on Friday and Saturday. It's in a bar, attached to a dining room, so I am contemplating using an SD-5 for the drums, a Hammond SK-1 on top for the organ and left hand
and a Roland synth over an electric piano on the right hand.
Frankly, part of the reason will be for looks. I'll also have a double neck, a Strat, a nylon string, a jazz box and a hi bred, with a pick-up and piezo. And, yes, if the tune(s) and crowd requires it, I may use the arranger function occasionally. And, yes, the equipment will stay on the band stand.
Look, rarely is any situation ideal. If it were, I'd be making $50,000 a night playing fusion.
I am not particularly fond of my restaurant gigs, and it's hard to get off on playing music to be used to sell paint. But to not realize how lucky I am to be making a great living doing all the things I love would be silly.
For me, as the poster boy for those who are entertainment skills shy, I'm satisfied playing guitar and keyboards without the help of an arranger. That's because I'm now in a dining room, playing 2nd fiddle to a ham sandwich.
However, when I want to do a film score rough quickly, with complete orchestration, the arranger fits the bill. In fact, many people think the rough is the final product.
For me to bemoan the fact that I don't play what I like would be really ungrateful of the opportunities I've had.
So, at my age (too old to change), I'm gonna play any damn thing I want to, any way I want to.
You should, too.
Russ (the grump) Lay