"Hawaii is an island chain and each one is unique and your pick will make a huge difference to your trip
Oahu - the commercial isle, with skyscrapers and many people. Plus Waikiki beach, north shore, Pearl Harbour, and filming locations.
Maui - the honeymoon isle, big hotels, expensive, nice beaches, great scenery
Kauai - the garden isle, green, less commercial with wonderful beaches
Hawaii - the big island, dramatic volcanic scenery, quiet (although much more developed than first time we went), active volcano, amazing beaches".
This comment from Onthegrid sums up the Hawaiian Islands pretty well.
Many people do fly from the West Coast to Oahu which is where Waikiki Beach is; its really America on Sea. High rises abound but the island of Oahu is also not without its charm and away from the city of Honolulu its a lot quieter in feel".
Like the Galapagos Islands there are no direct flights from the UK so they are not necessarily any easier to arrive at either. Travelers must fly from mainland Ecuador to the Galapagos Island (these are owned by Ecuador). You would have to break the journey overnight in LA or SF for both for arrival and departing from the islands. Its a further 6 or so hours on from these West Coast cities to Oahu.
You would also have to take a flight to travel between islands and there's only one inter island carrier (Hawaiian) so fares can be quite expensive.