For the record, I don't "hate" Avatar myself. It's a technological achievement and an entertaining ride. But that's about where it ends for me.
I simply take issue with people over selling it as "amazing" et al. It's a fun but mindless CGI filled popcorn flick. In that context I'd probably give it an 8...maybe 8.5 out of 10. In an overall film context probably closer to 5 out of 10.
Good popcorn flick, poor film.
As for Pi, it felt to me like it was trying to be more than simply a "spiritual" Avatar and fell flat on it's face doing so. It's not even that good of a special effects/"popcorn" flick. Either it needed added depth to be a better film or it needed to be more entertaining to be a better popcorn flick.
It had two personalities, neither of which in the end stood out or was particularly intriguing IMO.