First off, I assume you know the Paradise is totally nonsmoking, no exceptions, and they are serious about it - anyone caught indulging is put off at the next port & must make their own way home, no reimbursement.
That said, I toured Paradise last summer and found the decor typical of Carnival, a bit dark-colored but pleasant, lots of fun touches. Although I have not been on cruise ships that smelled bad by any stretch, the air on Paradise is definitely different, very clean and odor-free (due to the nonsmoking).
Carnival is a good first cruise for many people; if you enjoy a choice of lots of activities, some silly and others just pleasurable, you should have a good time. Just don't smoke! [img]/infopop/emoticons/icon_cool.gif[/img]