Is there a limitation regarding the number of items in a batch request?
Simplified JSON does not have any limitation on the number of items within a batch. However, you may be limited by other factors such as the limitation of the size of the message accepted by the server, i.e. 65535 bytes.(64k)
This question was first asked in an Introduction to the Elektron WebSocket API webinar (29th of Nov). Please see here: Introduction to the Elektron WebSocket API