Those that purchased the game here before the Steam release, should get Steam keys. Otherwise, you are just making your Itch supporters feel cheated out of their money. We have to buy a whole nother copy of the game just to access these new features, while new purchasers only have to buy one copy. That isn't cool and you know that, you even said "I understand that this might be disappointing to those who purchased the initial release on itch.io and can't access features that are using Steam, but moving forward development will be a lot smoother with the tools that are available on the Steam platform." Despite that, you just justify it with Steam being better for the future of the game. However, you have no intention of giving your Itch supporters access, unless they give you more money. There is no "might", we are disappointed and you should compensate the Itch supporters. If this is the type of tomfoolery you want to pull on us, don't expect us to buy your games ever again!
The fact that Itch supporters paid for the game before any Steam announcements were ever made, is why we feel cheated. The price isn't the problem, it is us being told that we are going to get an update later than those that purchased the game as of right now. Also, we are not going to be able to experience the new features regardless of the new update because they are exclusive to Steam. It is poor practice to do this, since this will divide the Itch supporters and the Steam supporters. The Itch supporters will get disappointed and get an inferior version of the game, while the Steam supporters will be carefree and get the best version of the game. The fix is simple, give Steam keys to the early buyers of the game on Itch. Otherwise, it is clear the developer is greedy. There is no other reason to be making people that owned the game prior to the Steam release, to buy it again. Read the other comments, I am not the only one that thinks this.