4K@60 FPS doesn't win at filming at night. It just looks way grainier and blurrier with that at night. I have a 'DJI Mavic 3 Pro' that has a 'Night Mode'. That mode goes to 4K@30 FPS at max. And the matter of fact is that filming at nights looks...
The down cameras stabilise the drone very well.
But when the target is drifting and rocking on waves, the drone is going to move around quite a lot to follow the target.