Wall of Blossoms would be good.

Bioshift to move counters from one thing to another before it gets killed, or to land a surprise hit

how do you add C15 cards? I can't put my Arjun, the Shifting Flame as my commander

Paradox Haze will double your +1/+1 counters each turn... to me it is a must add!

P.S. I love this deck and give it +1.

I might have to build one myself.

ZeroX, Ezuri adds counters at the beginning of combat, not upkeep. Though Paradox Haze is a neat card.

my bad... it just seems like a power that would activate during upkeep... though, at the beginning of combat is better.

if it were on upkeep, Paradox Haze would be super busted with him.

Evacuation would allow you to recast all of your dudes, but be brutal to you opponents. Inundate would allow the same but you get to keep some of your creatures, hopefully the ones with the +1/+1 counters.

Mass Polymorph would be cool for gaining tons of Exp.

Curse of the Swine will allow you to kill meddlesome creatures and replace your own little creatures with more little creatures and gain more Exp.

just some more thoughts.

Aluren and Cloudstone Curio all me to gain infinite experience counters.