Twilight Princess was far from huge. When you compare it between the three 3-D games it is the third smallest overworld. However, size did not change the fact that it was the most diverse of them. Twilight Princess only seemed huge because unlike the N64, the Gamecube could take advantage of camera angles to make many places that were far off appear from the distance, increasing the size in your eyes.
However, what did this overworld had to offer? It didn't offer much but it was a step in the right direction for a really great overworld. The problem was that it lacked the excitement and enemy amount of Termina Field and didn't have the expansion of the Great Sea. However, the overworld wasn't just some very slow sailing, it also wasn't of cramped.
Hyrule Field in TP did evolve as you traveled through it and that makes it very good. There are also very interesting secret dungeons hidden throughout it that gives it a good charm. Though the enemies were easy as heck, the raining Kargorok and the riding Bublins were very fun to fight while on horseback.
So no, TP's Hyrule wasn't huge, it just had a lot of great stuff in it.