Well first off max speed is meaningless, in my opinion it shouldn't be there!
The 5hz data is very up and down, like a sawtooth, possibly due to noise and/or 3D response. So max speed gives you speed + noise.
A 1sec average is much more meaningful as it averages out the extremes.
My speed sailing settings.

So I think try changing this setting.
If you want to keep track of distance and 1sec average on the water, set the speed genie really low, around 5kts.
That way you'll see current speed above 5kts, but it will scroll below 5kts.
So set "AVG MSEC" to 1.
Leave "RSLT 1A/1B" as is, then change "TOP" to "X" for the rest.
If you don't need the time change "RSLT TIME" to an X as well.
I think that should give you what you want. It should show speed while sailing, and give distance and 1s average when you stop.