I'll agree with peoples suggestion about the Southern itinerary but your question was only Eastern or Western.
If you want outside the parameters then:
Mediterranean, Tahiti, Alaska, Hawaii. My personal opinion is that one Caribbean island begins to look like the other after a couple of visits. There are a myriad of places to go on a cruise and a whole world to see. Now that you have the cruise addiction you can put it to good use and see the world and satisfy the addiction while you do it.
Take care and have fun cruising: Wherever you do it.