With Chapel, I would most certainly have gone Possession. You should very quickly get to the point where you are multi turn possessing your opponent. At which point you want your deck to be a pile of **** and are happily greening off of your opponents deck. Of course if you both imploy that strategy it becomes a degenerate game where neither player wants a good deck because the other player will get to use the deck more often.
I suppose with your game, you really want a strong engine. To do this you need a few things. First, you need to Chapel away your starting cards to make your engine consistent. You did that. What you didn't do was try to immediately ramp up to double province. To do this, you have nobles for +action, CR for +Card and +buy, and mint to increase money in deck. I would suggest using a single council room, Tribute with $5, tons of Nobles, and a single Gold minted into more.
Note that this isn't how I would play due to Possession, but it's a general gist of how I might play the engine.
*Edited to talk about the engine*
