If you need some more mana Ramp:
Gyre Sage would do a great job.
Then, on the first look it seems like you want to win with attacks, what about
Champion of Lambholt to shut down blockers?
about your land base, it may seem a good idea using all the storage lands with atraxa. BUT this means you are heavy dependant on atraxa, especially for the lands with depletion counters. Removing your commander, or morph him with cards like
Darksteel Mutation could break your neck. I don't want to way that its a bad idea, I just want to make sure you're aware of this problem.
If you want to improve your mana base: the most Check lands are cheap. Depending on your budget I would battle lands and bond lands then.
Shock and fetch lands may seem nice, but I think before you invest money for them, there are other parts of the deck that could be improved.
Depending on the utility lands used in your playgroup, it could be worth adding a land with the ability to remove them. The budget version would be Ghost Quater, the best would be
Strip Mine. My personal prefered choice here is
Tectonic Edge. The restrictions are usually okay, unless you want to combo with the land, it has no big down sides, and the price is okay.
Btw, I'm not sure about
Djinn of Wishes. I know that this card has a high potential, but without options like
Sensei's Divining Top or
Scroll Rack to manipulate your topdeck, you're very dependant on your luck.