I cannot tell you how happy that I am that blue/red decks are great in Standard right now. A Jeskai versus Grixis Pro Tour final in Standard is like a second Christmas to me. That said, I think that now is a better time to be selling off of many cards in the deck than buying in.
Kaladesh has a lot of powerful cards, and as such it's going to be very difficult for specific cards from the set to hold value given the inclusion of Kaladesh Inventions. Hype around Spirebluff Canal decks and the fact that we are far from peak supply suggest to me that we have already seen the short term ceiling. As such, I would definitely try to sell any Canals that I wasn't playing.
While it is true that Spirebluff Canal is also a great card for Modern, that demand simply does not justify a $10 price tag under these conditions. One only needs to look at the price history of Thought-Knot Seer to know where this one is going.