I think that Yangmingshan is really a good place to visit in Taipei.
If you go to the same place at different season and time, you will get a different feeling and different view of it.
I've visited Yangmingshan in rain, and I find it beautiful...and very romantic...although I hate the humid weather...
I like Yangmingshan, but I hate the traffic there...especially during weekends and holidays...there are always lots of people crowded there. Last time I went to Yangmingshan with my family...we went to a chinese food restaurant,
it is cheap to eat there, and the ½Þ¦å´ö they offer is really delicious...(you can refill for free...) but I forgot the name of the restaurant...