Thanks for the feedback!
With regards to the slanting horizon, didnt really noticed it until you have brought it up. Depended on the digital level inbuilt the 60D, guess it's not that accurate after all.
For #1, #2 and #4, what was cropped out from the frame were distractions that I felt would draw attention from the centerpieces. Nevertheless, will give it another try when I'm dropping by the Esplanade again