Kill gold
I'll start by saying as a disclaimer that i don't like going YOLO and that i much preferred a more controlled playstyle. I may be in the minority that's why i expect a whole lot of downvote :) but I would rather go 5/1 than 12/8 ooh and btw it's better for my team too...
So....The problem is that people are incentivised to go YOLO and to have ratios of 12/8 rather than 5/1, for 3 reason:
1° they receive (12-5)*300 = 2100 gold more gold 2° the drawback that the enemy team also receive 2100 more gold is kind of invisible, you don't see a big +300 every time you die, so you might not really realize it, or at least it's easy to forget 3° what you gain (the gold) is entirely for you making you super strong (and most people like to be strong, see the whole KS non sense), on the other hand, what you give might not even hurt you, (let say you went 5/5 in lane against an assasin, it's probably your adc who will suffer from the 5 kill the assasin got, not you). Sure you might loose because of it but most people seem to care more about carrying hard personally rather than winning as a team
so, those incentive kind of send a mixed message, ofc diamond+ when playing in ranked know what's best and will probably not fall for that but the majority of players don't play in ranked, even less in diamond +
My proposition is thus that you steal 150 from the opponnent rather than receiving 300 when you kill someone.
If you get a clean kill you still end up with a 300 differential, if you trade kill you end up balancing the book, but at least you cannot snowball out of control by trading your life, if you want to snowball you have to get clean kills.
Their might be some balancing issue cause it might favour low economy champ but it's not a more insurmontable shift than what we got 3 time this season (AP item, juggernaug, ad item)
In the end it might also promote a more controlled, objective based game where kills are a mean to achieve objectives rather than an objective in itself.