I find spacing and ball movement a lot more interesting than isolations, post-ups, and a bunch of guys hanging out in the lane, but that's just me.
I suppose it's all about what style of play you find most appealing.
To me, the most fun to watch team I can remember is the 2014 Spurs, followed by the 2010 Suns. The 2011 Mavericks were pretty fun as well.
I like free flowing, relatively fast paced, ball-movement basketball, with a healthy dose of pick and roll.
With all of that said, it does get irritating watching teams that seem to have no interest in creating any kind of shot other than a three pointer. When all you take is three pointers, statistically speaking there are going to be a lot of bricks, even if you end up scoring 120 points.
I would say, though, in terms of teams playing with a more analytical bent, the teams that try to generate 30-40 free throws a game (i.e. Harden Rockets) are a lot more annoying to watch than the teams that jack lots of threes.