Don't worry if your first decks don't beat some of the decks built by long time players, I say that everyone has about 15 bad decks to make before they start winning. Good going purchasing your first planeswalker, even if that ajani isn't the best. Also, this deck isn't standard, it is in fact legacy, might want to change that.

I just got an Ajani, Mentor of Heroes as well! Good stuff, eh?

Anyway, as far as offering help,

Take out the Wurm's Tooth . If you want lifegain there are much better ways to go about it. Essence Warden , Soul Warden , and Soul's Attendant all work really well because practically all decks play creatures and they are all cheaper than the artifact.

Cage of Hands is a fun alternative to Pacifism because you can move it around, but it's an old card and might be hard to find.

A more general piece of advice, lower your mana curve. You have something like 14 spells over 3 mana cost.

G/W is still one of my favorite deck types. Have fun!

Cryptolith Rite... 2-4 of them.

Oh, also Harmonize. Cool deck!