I wasn't sure what I would think about Dublin because I have heard a few people say that it's not what they were expecting and that it was a let down. Personally I loved it, but if you are looking for the traditional Irish experience, Dublin isn't the place to visit. It's more of a modern city and if you need to travel to places like Galway, Cork, Kerry, and Killarney to experience what a traditional Irish city is like.
I say this about every place that I visit, but London has hands down been my favorite place that I have visited so far. The city is massive, but the public transportation makes it so easy to get around. I have always seen myself working abroad somewhere in England, and I can definitely see myself living in London. The city is beautiful , the life is fast paced, and there are so many different neighborhoods of the city to cater to any type of person. My next two weekends will be spent in Cork, which will be nice to be able to relax after 7 straight weekends of traveling - it ends up getting so exhausting after awhile.