Best practice for external hubs

Well, when you aim at using many Aqara devices, I’d keep the hub at hand.
Matter appears not to be very stable for some users. Can’t say if it’s a generic issue.
On the other hand, not all Aqara zigbee devices are supported by the Aqara/Xiaomi apps.

As posted here the other day:
Most Aqara devices work via zigbee.
That requires the Aqara or Xiaomi Mi app. But do first take a look in the app store to check which devices are supported as zigbee devices: Aqara App for Homey | Homey
and
Xiaomi Mi Home App for Homey | Homey

Using an Aqara hub with Matter support, Aqara-supported devices become available as Matter devices, for which you don’t need a Homey app.
See also:

Other devices like the FP2 presence sensor and doorbell work via Wifi again, and then the [APP][Pro] HomeKit Controller for Homey (NL) app comes into play

You might also find this useful:

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