TTT's my favorite for much the same reason; it's tasked with neither the setup nor the resolution of the whole grand epic, which frees it to roar right through its plot. If I have any quibble with TTT, it's that Faramir's backstory was cut in the theatrical, so Faramir did nothing but grate on my nerves until I watched the EE and realized we'd only gotten half his story.

FOTR starts off very slow (as does the book, which was primarily why I made such little headway reading it in school), so I suppose they were going for some symmetry with a slow ending to ROTK. Which theoretically could be done; I'm just not sure copious amounts of slo-mo was the way to do it.