Handling of 32 and 128 bit uuids for BLE

Could it be an option for a first step to add a uuid128 field to ble_uuid_t(bluetooth.h) for non NRF52 boards ?

Yes, that sounds like a much better idea! I guess you could just make uuid a 16 byte array, and use type to decide if it was 128 bit or if just the first 2 bytes of it were used?

I'm not sure if that'd cause any problems down the line, but probably not that many...