Thanks for the feedback, Neil!
We added our own context-sensitive help system but ran out of time before the release to fully complete it with the content and it is hidden now. The system provides a better-integrated experience of getting help on any given block than the tooltips/help links. We will be opening it up shortly.
We have not given much thought on the ordering of the blocks within individual categories. The idea was to provide a search bar where we indexed all the blocks with keywords a user could use to find them. Additionally, there is a dynamic category in the toolbar called "Most Frequent". The system tracks the usage of every block and puts the most commonly used ones there. But I hear you, the ordering IS important for better user experience and we will revisit it.
The lower/upper casing of the blocks is intentional. Most if not all the Blockly blocks have the structural meaning/semantics, while ours are "functional", meaning they execute an API operation. Knowing where an API call takes place is important for our users, so we needed to have a differentiation.
The "null" block can come in handy when one must check a value received from an API call to see if it is there. Also, one could use it to wipe out a value when saving an object in the database.
Once again thank you for checking it out!
Regards,
Mark