the first is very interesting…i like the way the building lights and pedestrian lights stand out. as a subject, not sure it works, but the effect is interesting, almost of a sci-fi genre.
the 2nd doesn’t do anything for me…nothing to really keep the eye or a viewer’s interest.
as you say, the 3rd is a bit over-processed, but i still like it (doesn’t come across as an over-the-top hdr, like so many i see on the net).
I like the O’Connell Bridge picture. I think it would be even better if a few people had have been facing the camera and maybe if you could make out what is on the flag by brightening it up a bit.