Well, the first thing I can say is that you absolutely don't want to spend your whole time here in Goldenrod. I understand the charm it has, but... really, it's worth at least making your way north and spending the rest of your time in Ecruteak, as it's vastly superior. Honestly, even passing through is an experience... although, well, the theater is a good bet for most people. The museum's very nice as well, and you can generally come back after some time has passed and find a new exhibit.

The towers are also worth looking at, though I'm afraid that's all you may be doing for the Bell Tower, as it's off limits to the public for... whatever reason. I've been in it and I presume it was more exciting than it usually is because parts of it were on fire.