Evolution of vision
Vision is something that is very important if you wish to get good at League of Legends, and over the years its evolved. Remember when supports lugged around mostly wards like a caddy, but now they have a sightstone? Or when there were no trinkets and people complained about not buying wards? There is always a way to improve a game and vision is one key topic League of Legends could be improved upon.
Wards are very useful in gaining knowledge on areas where the map is normally dark and mysterious, but they are cumbersome. Sure there are sightstones for supports to make them more gold efficient (and some who decide to buy them as a jungler). For everybody else sometimes a game goes on so long the map gets darker and darker as players max out their items and trinkets get switched to prevent vision or glance at the enemy sneaking a baron. I think I have a solution for that.
The solution is fairly simple. Add a unique slot much like trinkets solely for holding a vision item such as Vision or Stealth wards (as well as a new possible item). This would hold 1 type of vision, but if you need say both a pink and a green ward, then one of those will take up a normal item slot as before. This would rid of problems in the late game for those who get ahead of the item curve or if the game goes on for too long. Trinkets would still be effective as in the early game they are free and there are choices to make with them.
The last point I would like to discuss is a new item. Clairvoyance and Scrying Orb are very underrated. Clairvoyance takes up a slot that doesn't help in combat in terms of healing, damage, damage reduction, an escape or chase potential. The Scrying Orb is often not picked up for the extra bit of "permanent" vision or denial of vision. Like with wards, I believe there should be a consumable item that scans an area of the map much like the spell and trinket.
As a final set of notes I have a few things I'd like to point out. I am not a developer and these thoughts are just that; possible ideas to help improve League that may or may not actually do so. Maybe the reason we don't have a vision slot besides trinket is so that in the late game when everyone has 6 items completed the game gets more hectic to allow for comebacks as well as possibly make the game more interesting.
If there were an item that served the same function as Scrying Orb and Clairvoyance, they would most likely become obsolete in a "professional" setting. Removal of the two previously mentioned might be best for making way of a new more useful consumable item, but it might not. I have not thought about this enough as, honestly, all of this was thought up as I was on the John moments ago.
If you have any sort of positive advice, counter, etc. please leave a comment. I'd be happy, as well as others might be, to hear.