This looks well-built. In these colors, I think you should consider playing all four Simic Charm - I'm uncertain whether or not this is correct though.

tchau204, your right Simic Charm is an all-star in this. Through the short while I have been working on this build I have found having a low threat count and having more than 4 direct support cards for creatures is not optimal. Simic Charm is super flexible though, but the sweet spot seems to be 2-3(two being more favorable) as 3 is do able but have had times when I want to draw other things specially a counterspell such as Dispel and on rare occasions that 5th land to turn Lumbering Falls into creature mode. If you would like to further discuss feel free to chat.