My thoughts on the proposed Preseason changes
As a disclaimer I would like to say that this is my opinion. You are welcome to your own. You are welcome to disagree. I just feel like I need to voice my opinion.
So, onto the meat. The tl;dr version is that I am apprehensive of the projected changes to Masteries, vision and the removal of the Mana Pot.
Masteries The "Keystone" masteries, as they are calling them, are one of the worst decisions you could make for the game, objectively and competitively. Allow me to explain. For this, I'm going to point the obvious finger at our good friends at Blizzard. At the drop of the World of Warcraft expansion for Cataclysm, they reworked their Talent system in to a nearly identical system to the one being proposed for Masteries (If I understand correctly). They did this for a nearly identical reason. They wanted to encourage decision making and diversity, and de-emphasize the maths. They wanted the choices to matter, and they wanted everyone's Paladin's to stop rolling the same thing every time. The problem with this, is that everyone's paladin is still the same, and there are no cost efficient ways to differentiate them. There is no recourse. Simply put, because the game is based upon mathematics, simplifying the math makes the mathematically superior decision the obvious choice. As opposed to being able to make use of the more outlier talents for your outlier champions. I would rather see more work done with the champions themselves to differentiate them, as the current talents feel more or less balanced, aside from the "Last nine dump" in utility, which feels underwhelming, where If you are taking utility, you want 21 in it, or you want to skip it for either offense or defense.
Vision Removing stealthed wards would de-emphasize vision importance, in my opinion, as it would remove the recourse available to the defensive team. The team that gains the momentum in this fashion secures their vision control as any wards placed (pinks) are immediately contestable. I'm going to point to our friends at valve with Dota 2 for a more reasonable compromise, to limit the amount of Green wards available in store to the team and allow them to regenerate over the course of the game to a cap (I don't think they do this anymore, but it's a nice compromise nonetheless). This would further emphasize the importance of Team communication. ("I intend to push my lane, may I buy one of our greens so that I can avoid a gank?")
Mana Pot I understand the idea behind removing this item. As stated, it is to allow you to better retool mana regeneration and mana as a desirable thing. But those stats are already desirable on their own. And I feel that a champion being mana starved unless they can navigate their way out of their early game into some items is a very important and distinct weakness to have. And having mana potions in the game helps to curb the harshness of that learning curve. You don't punish experienced players by removing this item. You punish new players for wanting to cast big, flashy and expensive spells. There must always be a bandaid solution to mistakes. Not ideal, but not the end of the world. And that is what Mana potions allow for in a world with mana starvation.
Conclusion All in all, this is a move to simplify the game further. Where as the game is already plenty simple, and oversimplification is a good way to see your competitive player base move on to other things. Furthermore, the real ramification is a potential lack of interest from new players.
As stated before, this is just my opinion. I will ask that things stay respectful in discussion