The most obvious problem with this deck starts right off from the deck name: Erayo colossus. What is the deck focused on? Putting a DSC into play or getting Erayo online? Personally I'd go w/ Erayo. I'd take out the DSC/Show and tell/Tinker and put in another Erayo plus win conditions and search. I'd just go the 4cc win conditions. Maybe an Exalted angel. Swords to plowshares would fit in well w/ Erayo, they're cheap. How about free spells? Gush, Frantic search, etc? How about this:
-3 DSC + 1 Erayo, Frantic search, Gush
-2 Show and tell +2 swords to plowshares
- 1 Tinker + 1 Exalted angel, maybe more
- 1 memory jar + 1 decree of justice
Speaking of DSC, Moat would be a nice way do deal with your opponents

That being the case, the Decrees become weaker and I'd just add angels. What year is it? Check your calendar!
Add Tundras/ Flooded strands and probably a Volcanic Island for REB out of the sideboard, etc. and get used to this deck...