it all depends upon what you want to do.
If you love gorgeous beaches with good snorkeling and amazing shopping then pick and Eastern Route.
If you want a bit more active route with good beaches, amazing snorkeling, Sting Rays, climbing waterfalls, Mayan ruins then pick the Western Route
I have done both several times and enjoy each for what it is. I don't know when you have to take the cruise, but , you may want to check out the current news on such "classic" western destinations as Grand Cayman and Montego Bay or Ocho Rios
as to the state of recovery from recent storms.
If someone going on the cruise is a shopper, then the eastern itinerary which would traditionally include St Thomas and St Martin features the two shopping capitals of the Caribbean.
Personally, since I like the beaches like Coki Beach on St Thomas and Dawn Beach on St Martin and Gram likes to get in a bit of the shopping, my personal preference would be the eastern itinerary.
I've done both and they are very nice but I prefer the Eastern. Not fond of Jamaica and really love the beaches and shopping in St. Thomas and St.Martin. I'm going back eastern this spring and except for Grand Cayman which is beautiful, I'd probably not do western again.
I have done both and would gladly do either again, but we like a mix of sea and land days--find this more relaxing. So check your itinerary . One of the highlights for us has been the "private island" where we were pampered as on ship on a gorgeous beach.
I support all comments above.