I have to say though, apart from the lens flare, those picture taken at night look pretty damn good to me. I'm still on the iphone 5s and the pictures off that are terrible at night, the X is going to be a massive upgrade for me...judging by the quality, I now know that I can safely leave my Nikon behind more often than not!
I'm not a pro photographer, more an amateur, do it as a hobby, like to take good pics on holidays and stuff etc. and I do see lens flare from my nikon during night photography, its normal, but its mostly orange, or bright yellowy flares, I haven't seen any distinctive green coloured spotty flares that look abnormal on my DSLR like those pics above, especially of that picture above with about 4 or 5 green spots randomly spread across the ground (the pic that you have circled in red)...that looks like the most unnatural flare I have ever seen...but like I said, I am no pro.