Hostname vs sysName in devices lists

We're adding most of our devices by IP addresses instead of hostname as we don't have DNS records for most of our networking equipment and are using an nmap script to try and add devices answering on their SNMP port with our known communities. Devices are listed and displayed by hostname instead of sysname pretty much everywhere in the UI meaning that by default all devices are listed by IP address. I get around this every time I update my install by changing the $device['hostname'] by $device['sysName'] in the $text variable generation in the html/includes/entities/device.inc.php file but is this something that could be configured in the config.php file or in the global settings instead of being manually adjusted after every update?

That would go a long way towards helping other people in my team manage our NMS

Thanks in advance