- Improved Arcane Blast
Can you imagine the HELL this would play in PvE?

- Slippery Blizzard
"New and improved Blizzard! Now gives your enemies the opportunity to escape it quicker!" I can see the appeal of a slippery surface as an untapped effect of ice, though. You've given me entrancing visions of making warlocks helplessly slide into the abyss in Eye of the Storm.

Not flawless ideas, but you're thinkin' and I like that!

I would really love Quick Invisibility! I would be fun to see mages popping in and out of view. It would go along with the “slippery glass cannon” model. And invisibility would get used whole a lot more, and make gameplay much more interesting!

I really like that Improved Slow Fall idea seems cool.

The reason your concept for Arcane Vortex cannot work is that it would require a ridiculous amount of work by the servers. As thy currently work, Alter Time and the hourglass mechanic on Murozond tell the servers to take a snapshot of your current location, status and condition and to revert you back to that single saved moment at the spell's end or on demand, respectively. Your Arcane Vortex would require the servers to maintain a constantly updating three-second history of every action by every character in the world just in case a mage casts this, so it can revert the target to the appropriate conditions.