Not sure if you want a list of things I'd like to do different or 12 things specifically but:
Doing away with lanes entirely, and making the game heavily objective and jungle base. I've played War3 maps for years, and I'd also really love to bring back this old Mission system I had a lot of fun with from an old AoS. Reasonably, I'd like to take the best qualities from every moba and mash them into one, along with the stuff we think of.
We have a vision where we want to remove a lot of the annoying and hard to get into portions of mobas. That includes traditional last hitting, laning, etc. We have two layers to the project. You can play the moba, and really get into the game; or you can read the lore and get immersed in the world. Hopefully people will do both, if even one person ends up liking what we make, I'll be happy.
No one uses flat mana, everyone has their own resources, although some people share them. At launch, we want 20 heroes with mostly different ones. Things include Sharpness of your weapon, that dulls or sharpens based on how you use your abilities, and effects your abilities offensively and defensively. Momentum, that builds up as you move, and rapidly degens, giving you more speed and having your abilities have additional movespeed to damage scaling, etc.
We have a full storyline going on, and have artists and voice actors as well. Its been about two years worth of theorycrafting and building between my group, and we're finally at a place where we're happy enough with how everything is to make it. But I cannot create this alone, and no one else in my group knows how to use World Editor.
I can always give more information here, in pms, or through skype. And that goes for anyone interested. Preferably, I'd like at least one person to help us out. Two would be beautiful. In the coming weeks, we want to do a three day weekend game-jam kinda thing, where we knock it out.