Wiggyx- Sorry you didn't enjoy your cruise, but many of your complaints are only subjective. To insinuate anyone is a donkey that enjoyed any of the entertainment is a bit disingenuous on your part.
You mentioned you needed to write a letter to Virgin for not telling you about the service charges. Well shame on you for not doing your home work. Too often people see a "cheap" cruise offered and all they care about is the "cheap" price. It doesn't matter to them whether this cruise line is a good fit for them, or how old the ship is, they just want that "cheap" price. The Costa Allegra is one of the smallest and oldest ships in the Costa fleet. The smallest cabins on the ship are 153sq ft. I have stayed in cabins as small as 119sq ft. And while they were smaller, still were adequate. You could of opted for a 330sq ft mini suite when you booked. You've cruised before, so you should know all you had to do was ask your cabin steward to push your beds together.
The majority of the major cruise lines are charging the service charges to your on board account. Most still give you an option to remove them or adjust them. Most people don't, because they realize how hard the crew work, and that they work for tips only. Adding 15% onto the bar tab is nothing new, and all the cruise lines do that also. They've been doing it for at least 15 years. The bar was crowded during happy hour? What did you expect? As for the cost of drinks, it is right in line with other cruise lines, and also in line with land restaurant/bars. I've been to Europe twice in the past six months and paid the same if not more for beers and cokes.
The only thing legitimate in your complaint is brown water in the shower. Hopefully that was fixed.