We can’t answer this for certain yet, so we’d say if you want the game on Steam - it’s best to wait for now. $15 USD is the final price and it’s not going to change, so there’s no need to worry about missing out on a discount or anything by waiting to order later.
Though the KS-version is exclusive to the KS backers and it’d be unfair for us to sell that outside KS now, the deluxe version is still going to be available to everyone later as a purchasable DLC and it’s going to have a lot of extra content! We hope that makes up for it a bit!