What are your suggestions for a cruise wedding?

We’re thinking about doing a cruise wedding next year. Either getting married on or off the ship, then going on a mini cruise to somewhere with a few family members, then doing the honeymoon thing.

What are your experiences with cruise weddings? If you’ve been on one, what are some positives and negatives? What cruise line would be best for this? Are the prices fair? What should I include with the wedding? Where should the cruise takes us? Any other good ideas or plans?