Stealth and... Clairvoyance?

TL;DR Reincarnating Clairvoyance can help to deal with invisibility being a bad mechanic.

Stealth used to be universally countered by true sight. Any champion that used stealth could be seen by towers and by pink wards. This way, in encounters were you absolutely needed to be able to keep track of the opponent in fights, you could drop a pink ward to see them coming. This offered a countermeasure to stealth.

Riot removed this functionality as pink wards were changed into control wards, and they adjusted the way stealth works through the distinction of camouflage and invisibility, because they believed it wasn't right for stealth reliant champions to have their kits countered by a very cheap consumable item (pink wards).

Unfortunately, this means there is very, very little counterplay available to most champions in order to deal with invisibility. If Vayne pops her ult and begins tumbling around, or when Kha'Zix uses his ult when he's fighting, even if you don't rely on point and click, you're still relying on extremely iffy guess-work to attempt to land skillshots on enemies that you can't see. While stealth champions may have had "too much" or "too easily accessed" counterplay, now, invisibility is overbearing for much of the roster.

There used to be a summoner spell, clairvoyance, that allowed someone to reveal a portion of the map globally. This had its uses, such as checking out the opponent's starting items before leaving the fountain, or checking for where their jungler was in their clear, or for mind games in an attempt to convince the opponent that a certain bush isn't occupied or warded.

I'm wondering if a reincarnation of Clairvoyance could be used to offer an additional means of responding to invisibility. Clairvoyance: 90 second CD? 120 second CD? Briefly reveal a portion of the map with sight for 5 seconds. Upon activation, if a champion is seen, inflicts a debuff that lasts for 8 seconds, providing vision of them.

This means that, by giving up a summoner spell, there would be the ability to find invisible champions. However, if they are already invisible, you can't use it to find them in the middle of the fight. It also provides the user with flexibility, at a cost: use it to gain information, lose it for a fight when you might need it.