Actually, due to the short range of Zigbee radio signals, it is more important to have a few known good Zigbee Router devices if you have a small Zigbee network with some battery-powered devices.
A lot of people that is just starting with Zigbee do not understand that it relies on mesh networks and/or that battery-powered devices do not act as Zigbee Router devices so they only buy a Zigbee Coordinator and a bunch of battery-powered devices and then wonder why they the loose connection.
Again, highly recommend you read and try to follow through all of these best practice tips → Zigbee networks: how to guide for avoiding interference and optimize for getting better range + coverage
That is currently the generally recommended firmware because it is known to be very stable, however, later firmware will have later bug-fixes that might offer better compatibility with some newer devices.
So any newer firmware all the way up 7.3.0.0 that has specifically been built for the Sonoff ZBDongle-Z should also work, but they has not been tested as well to can not be said to mature or how stable.
If you have that much problem with those specific Aqara devices then it is worth open an issue to Home Assistant core to get the attention of ZHA developers → Issues · home-assistant/core · GitHub
See what is needed in new issues → https://www.home-assistant.io/integrations/zha#reporting-issues
To cleaify, I’m not a developer of ZHA or zigpy, but I did help contribute to documentation + readme files. Please note ZHA documentation are still in dire need of more people contributing improvements to it: