Oh man, that's a bummer. Last time we went was probably right after Xmas. It was a weekday (school out, but before the start of work vacation in Jpn), but the place was really buzzing esp at night. I can understand it being underwhelming if the place was dead. The evening illumination was the main attraction, but sorry you couldn't stick around for that. Anyways, as I said, HTB is not everyone's cup of tea.