I feel that hammerhead is the best device and in terms of everything. This is the reason why developers are working on Android Oreo ROM and still, it is the best device. I will try to make a list of Android Oreo ROM's.
I feel that some of the best ROM are not available on XDA, and it is available outside of XDA because of eta issues or bugs fixes, but I will try to maintain the list of ROM'.
AOSP 8.0 Hammerhead
Liquid Remix Oreo 8.1
If you find any other oreo ROM's, then please feel free to comment below.