We're going to have another Williams vs Williams in the early rounds. It's the trend nowadays.
I hope it happens in every tournament they play. Maybe then, when both of the them are in danger of dropping from top50, we are going to see something that doesn't scream "training session"?
If not Serena-Venus, then maybe Serena-Mladenovic?
Also Halep - Mladenovic/Vondrousova/Ostapenko would be interesting.
Azarenka - Cibulkova/Sabalenka?