I think that they should have Tetra help you more. Link has a sidekick in almost half of the games. Navi, Tatl, Ezlo, Fi, Midna, etc. In The Wind Waker, Tetra sneaks a stone into your pocket that helps with communication. But you see it in action a few times. What they should do is if you Target an enemy, a little Tetra Icon flashes and if you press that button, Tetra tells you about that enemy. But seeing how Tetra is, well, Tetra, she would probably say it in some mean way. "What??? You have got to be kidding me? You don't know a thing about the Wallmaster?!?! Then I guess that you don't know if you get too close and grab you by your neck. Now get back to work. And step on it.
I've never had any trouble at finding sunken treasure. Sometimes, I time my the brakes just right, and I stop right onto of the treasure. But a beacon system could be nice. And a little tougher battles with the Bosses. Hopefully the Nintendo Gallery and Tingle Statues Quests will remain.