European City Stag Do
Perhaps you would like a trip to a place like Amsterdam where you can be as wild as you like or just go to soak up the atmosphere. You can have a cultured break and visit museums or do any of the number of things that Amsterdam is notorious for. The same with Ibiza, it is notorious for its clubs and dance scene so if this is your type of thing then Ibiza might be good for you.
If you like the thought of going to a European country but would prefer something a bit quieter then you could go for a beach trip to somewhere in Spain or Greece or a more cultural trip to Paris or somewhere in Italy, where you can visit museums and tourist sites but still have a good night life.