Aqara hub only compatible with aqara zigbee devices. But then latest M3 Hub is matter compatible. So it can work with any matter devices

It really depends, Aqara have most of what you wanted, but Aqara’s price now is on the high side. I get most of my aqara from taobao.

Matter compatible device is still not that easy to find in local market.

If prices is a concern u may want to take a look at tuya compatible devices, they are relatively affordable but then quality wise is a hit or miss.

If you have time and like to tinker around then Homeasistance is the way to go due to its wide compatibility and can combine most smart product.

Aqara devices regional lock has been implementing for few years, although you are still able to use it, the device response time could be suffer because device need to connect back to China.

Aqara if using Aqara app everything runs locally. Same with when integrate with matter. So no need connect to China.

I just use the aqara smart lock for my indoor door lock. Had to change the batteries after 3 years of usage. Pretty good IMO. Didn't give me any issue so far.

Mine was the older model Aqara N100.