I wouldn't go down to less than 2.  4 does seem a bit large when your wanting to win asap.  Against decks like 4c Control, tog, and gat, where their mana is so important, then wasting their red source, green source, or even black source, is that important to swing the game in your way, maybe stopping a game breaking play like yawgmoth's will.

neither masticore nor RotW should be played.  there just begging to be mana-drained.

Another thing is this, if your playing aginst slavery, or whatever brown.dec,you'll want to cast null rod w/ oxidize back up or logic back up?

Counters > condionary spells.

It does need to be in the board.  I'd also suggest throwing in red for:
Red Elemental Blast, Artifact Mutation (instead of oxidize?), and or Flame Tongue Kavu if your meta is very aggro heavy.

Oxidize > Logic....are you kidding?

Lets break it down.  In a basic metagame, you have atleast three main decks you plan to see.  4cControl, Hulk, and of course a form of artifacts.  

What cards in 4cControl and hulk are an oxidize going to stop?  CoW?  Sure, maybe against slaver, oxidizing thier slaver might give you an extra turn, but wouldn't you rather just logic their thirst for knowledge that put the slaver in the yard?  Think it through, very few times, like 1/20, would I rather have a oxidize in hand than a logic.  Besides, your playing madness, you should have a nice sized yard and a nice dog to pitch your logic to.  I'll post my decklist and matchups later to help you out some more later, for now, I have to get back to work.