I think we will overlap in Maui
We are heading out in a few hours. Haleakala is an amazing experience at sunrise. I've heard sunset is great, too, but we haven't done that. Have you tried any of the tour groups? That's how we did it, as DH didn't want to drive somewhere unfamiliar in the dark. I think this was the one we did:
https://www.skylinehawaii.com/maui/haleakala-classic-sunrise-tour It looks as if they might be sold out, but you could always call and be added to a wait list. I know there are a couple other tours, too. Aloha!
We are signed up for this one, too! We've done Greece and Rome, but Croatia will be new. That's assuming DS's graduation doesn't force us to change cruises!
I suspect vaccinations will be required for international travel and cruises as well. I hope they are at least! We signed up for a summer 2022 cruise (above) and are counting on it