If I am seeing it correctly all Homematic devices added using the integration are added as entities and no devices are created. Therefore you can not add the devices to areas and you do not have them grouped together properly. Adding support for devices would help sorting devices and make it way easier.
Have a look at this post on some factors why I think this isn’t making progress.
I think the lack of fancy config-UI-options from Home Assistant would require a simplified HomeMaitc configuration, which would exclude users with complicated setups. The alternative would be to support both UI and yaml-configuration, but that would be a real pain to implement.