On-Body Flash Question

[MadMax1412]

Hi Guys,

A while back I was on a train which had a landing on the back of it. Due to the depth of the landing, I couldn't move back away from my subject (my daughter) very much.

From memory, I left the camera in either full-auto or in portrait mode as I decided that the backdrop would look nice, especially if it was a bit blurred.

In the first shot, the on-body flash wasn't used (f4, 1/1000th and ISO-400) and in the second shot, it was (f5.6, 1/200 and ISO-200). Do you think the 2nd shot looks too bright?

What would have been the better way to take these photos given I was using a Nikon D90 and a Nikkor DX AF-S 35mm f/1.8G prime lens? Should I have used the bracketing feature and gone +1 and -1 and somehow used software to merge them (I think that's how HDR works??).

Thanks in advance.
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