Change console-conf in my custom build image

I have just created my first custom built ubuntu core image. It includes my app, custom gadget plus cloud-init config, which configures my application. I also disabled custom-conf, so it doesn’t mess with my config. However, I also have some settings, which unfortunately have different values between each device. e.g username and password to external service. At this moment, I hard-coded it into cloud-init, but I was investigating if it is possible to edit console-conf to add additional step, where I can be prompted for a username and password. I checked that console-conf is python application, so I guess it could be possible to add it there ? Is it a valid way to do this ? Or maybe there is a better solution for it ?