Hey @dav!
A handy tool for troubleshooting/understanding denials and getting interfaces recommendations is snappy-debug. If you haven’t used it yet, do so and feel free to ask any questions here so we can help!
If you only need to monitor sensors, can the network-manager-observe interface be used instead? network-manager is a privileged interface which allows to configure networking and this is not your use case iiuc.
Following the same reasoning, can you please explain why you need gpio-control? It allows privileged access to hardware so probably gpio is enough?
In general, could you please explain the reason for each interface you would like auto-connection? In case you are interested or have further questions, you can read more about our Process for aliases, auto-connections and tracks