Cardiff by night

You do not mention if you agitated during development. If you did, next time don't. Stand developing gives the best results for negatives exposed at night because the developer on the highlights exhausts and so the highlights don't burn out while the shadow detail develops.
For film I use HP5+ and expose at f16 for between 60 to 90 seconds, depending on how much streetlight and type of street light (longer for sodium lighting).

Hope I haven't tried teaching gran to suck eggs!

I agitated quite a bit, never realised about standing development. Will do next time. I've just printed it and there's a hell of alot more detail there than in this scan, answered my own question really!

I would also recommend the book, Night Photography by Andrew Sanderson ISBN 1 902538 12 9

If you wish to use stand development care is called for because with some developers you will get bromide drag...uneven development. The best developer I have ever used for stand developing is Pyrocat HD or MC.... The developing agent is cathecol. It is a staining developer that is especially well suited to scenes with a light source in them. Go to unblinkingeye.com and read up on it. The formulator of Pyrocat HD...Mr. Sandy King...has written a sizable article on the developer.

Having said all that I think this photograph is very nicely exposed. You captured the light perfectly and it imparts the atmosphere very well.