How can you compare the two? Bruce Willis' character was the MAIN character for the movie, along with Osment, and after all the ghost stuff they go through together, you find out he was unknowingly one, too, and then they go back through the movie showing all the hints peppered throughout that showed he was a ghost, it was a genuine shock and it worked.
Tate was an under developed side character who was a boring business woman going on about a clean energy project, who was the most random sex scene ever, with no chemistry or heat between her and Bale, then just lingers in the background, until she's revealed as Talia, and then dies.