I think it's a good idea.
When my mast was out three years ago, I put in coax and power cabling for a PTZ camera to be hung below the radar
dome, so 10 meters above the waterline.
My idea was not picking through shallows (although that seems also like a good idea), but to enhance visual watchkeeping with a better view ahead, and also, especially, for docking
. In addition, I intended to feed the video feed to my bulkhead 32" monitor
so that I could see something about what is going on outside, from my nav table.
I have so far not gotten around to installing the actual camera, but this winter might be the trick at last.
Most modern chartplotter
MFD's allow you to display video. Those very bright displays should give a fine image. I don't think very high resolution is necessary to get very useful visual information. Especially docking! Which is a PITA in a boat like mine (with 16' beam) where you can't see the dock
at all from the helm