Well, maybe we can bet on weather? Just kidding.
Adding more crypto bets sounds like a good idea.
If you're looking for sports events which aren't cancelled yet, take a look at Australia. Their football, rugby and Aussie rules leagues is still in play. I'm not sure how many people would be interested, but when there is simply no more sports event, probably it would get more or less interest.
Also, on Flashscore app I see some esports events available, maybe it can be another option.