I do have to say that, in my own opinion, Phantom Hourglass was easier. However, comma, that doesn't mean that it's not as good as TMC. In fact, I enjoyed PH much more. TMC probably had the most adorable Princess Zelda I've ever seen, but PH had more characters with more development. Linebeck and Ciela were both great additions to the games. The items were a lot better, too... or at least, that's what I think. I really enjoyed the unique uses for various items in PH, and I really liked that they even brought back the hammer and the turtles, heh.
But still, though PH had a lot to offer, it was easier than TMC. PH was more annoying than difficult. TMC, while being one of the easiest Zelda games, still offered a tiny bit of difficulty here and there, moreso than PH did.