It doesn’t matter where you go, it’s the mates you are with that make it. Go where the wallet takes you, big cities (apart from the old Eastern bloc countries) are generally expensive all year round but Malaga is relatively cheap and has brilliant bars and restaurants. Holiday resorts are less expensive out of season if you are on a budget, Alvor (amongst many others mentioned on here) in Portugal is great and the Euro bar lives up to its name.
Bit of advice, get your flights booked asap, take hand luggage and look at booking a Villa or apartments through Owners Direct, Air BnB, etc online, it can save you a good wedge.