The problem with this game! Snowball effect and XP

Riot over the years have make this game more and more less snowball! and that ok! but atm the new patches always reduce the snowball effect to almost 0! what do i mean

I was playing a game (Jungle) i was shaco i was lvl 10 with 5 kills and 2 assists 70 minions and i check the enemy jungler he was 0-2-0 -65 minions lvl 10...

And i was like what??? so i create for my team 7 kills and i am still the same lvl with someone that did nothing?

This is bad..and i notice it that again when i was playing top lane

So i kill someone and i notice that i got 10 xp...for real i got from a kill 10 xp so i kill someone i got 0 xp yeah i got gold but 0 xp and the enemy was the same lvl as me...

So that why the game have problems with champions that never really fall behind if you destroy them in lane or in jg because kills mean nothing in terms of outlvl someone

I remember that when you were taking FB you were getting a full lvl now you get 20 xp...i am not saying bring back the season 2 snowball that if you die once in lane you were lvl 2 and the enemy lvl 8 i am saying that if you destroy someone to feel the impact..because all this problem with yasuo and fiora and gp and more that people have that they say "i destroy him but he got one item and now i cant deal with him"

If the game was better in terms of how snowball work you wll have more level than this yasuo when you kill him 5 times but the game right now dosent allow that you kill him 5 times? at the best he will be lvl 6 and you lvl 7 so ofcourse it mean nothing when champions like him only need some farm

But if the game was different he would have been lvl 4 and you lvl 7 so now even if he got an item he is still useless so your IMPACT that you did and you skill you put to destroy him in lane now have a meaning....