Since its creative Id like to see features where you can press a button and remove the time and weather, so you could build your stuff on a sunny day forever. Than press the button again and the day/night with weather circle is active again.
Honestly, and some may not agree with me, I don't like that you can destroy a block with just a mouse click [in the fashion of destroying torches]; it makes things harder sometimes if you aren't good at clicking and not holding, and I sort of like the satisfaction of at least destroying blocks normally.
I'd love to see full client-side integration of WorldEdit (perhaps toggle-able to prevent people from messing up), an in-game toggle for Mobs, Time, Weather, and Insta-Break, and PLEASE, a hotkey for flying. I've died in the void so many times because I didn't know if I was flying or not.