I'd add, GLC, that we did not stay in any hotels. We rented a house in the Puna district (northeast coast) through VRBO for five nights and a guest cottage of sorts on the Kona coast for four. We just like having a bit more room and the ability to make a few meals. It worked out well for us.

While we saw a lot of cool things on the east coast, the town of Hilo left us a little meh. The farmers market is great and we had some good sushi one night, the town overall is kind of worn. I'm glad we stayed just outside of it.

In some ways, I like that the east coast doesn't feel very touristy, but if you're looking for a vacation-y feel, you might not like it.