Helicopters generally have superior cockpit visibility than planes, let alone that yes, if you bank a floatplane, a float can also block your view. Helicopters can also fly tighter and more direct approaches. I recall on one of my early helicopter solo cross countries, flying into an airport I knew very well as a fixed wing pilot. The tower just told me to remain clear of the approach path to the runway, and otherwise approach as I wished - I was spooked! If multiple helicopters are operating into a non heliport/airport environment, they're usually "on the job", know each other are there, and self coordinating traffic.
For my experience, if a body of water has a commercial operation, or even more than one, there is usually excellent voluntary traffic cooperation, the operator(s) recognize the safety benefits from agreeing informally on a traffic pattern, and in such case, the experienced float pilots will all see the merits of the same approach in given conditions, and the inexperienced float pilots will follow that lead. complications arise when an "outsider" arrives to the area, unaware of a private traffic pattern.
Even the most mundane water landing will have concentration demands equal to the most demanding runway landing. Wheel pilots recognize that with experience and type familiarity, wheel landings can get to the point when they require only minimal demands on concentration. Any water landing involves determining the wind direction, and micro local variations, water conditions ('cause the runway is always moving), surface traffic and hazards, and cockpit checks (particularly for amphibians). So task saturation of a less experienced floatplane pilot is reached more quickly during a water approach, than landplane pilots would anticipate. Add to that glassy water, or high waves or winds, and you're really focused!