Basically these are flashrouters fully compatible with VPN service installed. I recently installed PureVPN on one of them. Actually bought it in BF with 5 years subscription in $1.15 /m limited time...

It's a weakness in WPA2 protocol so unless TP-Link released the patch for devices we can't avoid it. But, being affected by it is remote because attacker needs to be in the close proximity.

I don't think it's because of router because bandwidth and speed remains same from the provider. Software can be the issue here with compatibility.

There aren't many changes except RP-SMA. Not I found any.