Basically you're talking about using the fishmans as "Side Fills" which are used on bigger
stage setups. The times I've used it with bands they tend to have a general FOH like mix
in them. This does work quite well, and there's nothing wrong with it, however, I
generally use them in addition to wedge monitoring.
If the band are happy with
just the fishmans as a monitor from the side of the stage, then that's all cool
But I'd ask
Music Teacher, Isle of Man