I know we all have our own way to entertain, but even after reading all the above, I don't know why anyone would get bored playing instrumentals ... JMHO ...
Me neither, Tony...plus it's always an interesting challenge to find tunes that work well as instrumentals...not all songs can manage that transition.
We have a remarkable keyboard at our disposal that literally allows for "instant" arranging (or, re-arranging, if you will) so if we can't manage to make a tune interesting, it isn't the instrument's fault.
Ian