The last level is pretty straight forward as far as the jumping goes. I found the most difficult jumping "level" to be the Goron mines.
The first half of the game was defnitely its strongest in my opinion. I won't give any spoilers, but I just found that the discovery/adventure aspects to be of higher quality. After the second half it just started to become more of a "get through this part quickly" thing.
I've been doing a lot of the side quests and hidden caves as well finding bugs, etc. The game keeps tracking time even when you pause it with the Home button, so I'm at over 90 hours after having completed the last dungeon, but before killing the last boss. I forgot that I had a certain item that I could use and just quit out to come back to it later. Probably for the best anyway because there were a couple of other hidden areas I wanted to fart around in first - just in case the game would come to an abrupt end after that battle. I also still have to get the final special ability - I was playing late one night and just couldn't nail the howl down.
The reviewers that mentioned the graphics were "lacking" in this game are off their rockers. There are many aspects that don't push the envelope, but there are some really great visuals in Twilight Princess. Nintendo put in a lot of attention to detail.