I'm not playing WoW these days, but I wasn't very happy with the scenarios compared to real dungeons. Other people, however, loved them. I'd suggest running a bunch of scenarios while you still have 5 so you can see which category you fall into before canceling.

I've been back and forth with the long deadspots in content enough now that I just cancel when I get bored and resubscribe around mid October when all the holiday events start coming back. That gives me plenty of time to check out anything that might have happened while I was unsubbed {or see that nothing has happened and remind myself why I unsubbed in the first place, lol}.