This is where the idea comes from:
It would be practical to create a subflow. Not as an extra flow per se but as an extra group.
Nested Nodes | Vue Flow
It would simplify the editing very much. SplitInBatches it mostly very complicated to use.
The nested flow could also have a batch size here.
It solves the problem with the complicating SplitInBatches.
Maybe multiple nesting can also solve the problem with multiple SplitInBatches.