He said he was going to work on Creative mode some more. What do you guys think would be good in it?
The idea of Creative is essentially no mobs, and infinite items.
Originally, Creative is the version of the game that was before Alpha phase. It has much simpler lighting, no mobs, a finite map, instant digging/mining and infinite blocks, however the choice of blocks is much more limited. The idea of just creating and not surviving has persisted through today in the community.
I used to host servers where mobs would be off and everyone were OPs and we would create cities. I stopped hosting mainly because people got bored, people abused the OP privileges, people started dictating what should be built and not built... etc. Nowadays I only play in SSP, using mods like TooManyItems and CJB cheats in order to create a nice environment that lets me create whatever I want. Alone.