In a world were security gets more important each day, it would be very usefull to have some form of 2fa in place for web interface of the pbx (administrators). I would propose a google 2fa authentication code web client (I would suggest email verification, or, if one has the softphone installed on android, ios or windows, it could be generated with a code trough chat. Of course google 2fa would be great too. even better: led administrators or clients choose the form of 2fa A lot of businesses focus sing on iso certification would be very pleased. And 3cx too, as an additional security selling point.