When I import raw files, in my case from Nikon and Fujifilm cameras, I select an import preset:
The Reset button resets to the ACR/LR "Default" settings. The application of a preset will alter the default settings but doesn't change the built in "Default". You CAN change the Default camera by camera and ISO by ISO if you want. Or you can create and use presets as you are doing, but Reset always resets to Default. And Default and presets are separate with no cross-talk.
However, it would be pretty easy to apply your preset for the camera then go up to the Develop menu and select "Set Default Settings" which will change your default settings to those that match the preset. From then on, you won't need to apply a preset when importing. Also, if you want to edit the new "Default" you can change the settings and redo the Set Default Settings. You can also always go back to the original Adobe default settings if need be.
You can also check history ad go back to after the preset and before changes to get back to the imported state...