I'd say look over the list of Primary and Secondary Domains and update them if necessary. And that should be about it, unless you want an American Gods-style clash of old and new Gods.
Leviathans should be gruesome modern fears made manifest. And I'd come up with a common miracle that lets you make mortals forget about the supernatural, unless you want a setting where all these gods are coming out of the woodwork and making their case to the world.
Also, to be honest, you could probably go far by making the gods more serious and less silly overall. The God of energy would have more meaty and interesting story hooks than the God of Afros. Just saying. Although there could be humor in watching your Gods tangle with the legal system...