KSDisneyDad, thank you for being so clear! I 100% agree with your statements. Further it actually answers the OP's original question of "worth" not "cost" as others are trying to bring in. OP knows what $6k is and what she is asking is not how can I cruise cheaper but is DCL "worth" the additional dollars to cruise on DCL over other options.
Worth cannot be broken down into costs. Dictionary.com would disagree with you. So i agree with ilovetexas that, as I did in the beginning of this forum and like many others, you should put why you think DCL is "worth" the extra money. So have pointed out that DCL is not always more expensive but during the time OP wants to go it happens to be. RCL, Carnival, etc don't figure into answering her question.
Of course they do. The term worth is a term of measurement. In this case, since technically we can't decide whether or not a DCL cruise is "worth" $6,000 to the OP, all we can do is either tell her why we think it is worth it due to tangible items that we don't all agree on or tell her it's not worth it based on something we all experience in the same way...DOLLARS. A judgement based on dollars is going to necessitate comparison to like items....other cruise lines.
I applaud Carnival defenders and would challenge them like I have been challenged to provide proof of "worth" for sailing them vs. DCL to the OP not to me because I don't care. I have given my statements of worth as many others have. I even see RCL's worth debated in this string. I do not see any other lines "worth" vs. DCL defended.
Then you didn't read my original response to this thread. I said my kids loved BOTH lines. When I am cruising with my kids, that is WORTH a lot.
I think we can all use this as a bully pulpit to get our view of DCL vs. others out but that doesn't help answer OP's question.

We are all obviously Disney fans or we wouldn't be on this site so lets help OP with some facts not opinions. I include myself in that statement.