I love adoptable storage when it's available, think it was available on HTC phones where I can make the SD card and internal storage as one big storage. Obviously this take takes away the flexibility of using the SD card. But here is a great video which shows how to convert the G6 SD card to use as adoptable storage, better yet you have an option to allocate a percentage of your SD card as internal storage and remaining to be used as SD card.
https://youtu.be/N6pWo2U-Xuk
https://youtu.be/N6pWo2U-Xuk