I think you're forgetting that Ocarina isn't the best game ever. Wind Waker stands up far better than OoT does today, and when TWW came out it wasn't even a fraction as groundbreaking as Ocarina was. OoT has its place in history, but that's about it.
That being said, everything after the Master Sword in OoT was just straight dungeon crawling, so I don't think adding an Ice Temple would've broken it up that much. Though to be honest all I really want is for Nintendo to thaw Zora's Domain post-Water Temple like it was originally planned. It would've been nice, and it wouldn't really have changed anything (Aside from taking away the moral of "you can't save everyone", but then again I'm pretty sure I'm the only person who analyzes video games. so.)