Interesting subject indeed.
For all these years I've used a reverb that sounds good to my ears, plus delay that I always customize, so that it has one repeat only, barely separated from the original. Not loud enough to be intrusive, but enough to fatten the vocal.
Since I've had the Bose pa, I have reduced the effects greatly. Bose recommends that you use NO effects on the vocal and set the L1 processor to the type mic you are using. I've yet to come full circle and do that, but I find I can greatly reduce what I was used to hearing for so long, and get positive response from the audiences.
DonM