More Creative and Possibly Better Ways To Balance Champions

Why aren't champions ever balanced based on level? I know I just got a lot of people saying well duh its gonna either hurt champions that are zoned from experience or... That's all I got.

Just so Everyone knows:

I would like to create a discussion that hopefully will involve a @Riot employ, and the rest of the community, Over the Years I've noticed that champions can be broken in One or Two ways.

The First would be Champions themselves being over tuned which leads to direct nerfs that end up putting a champion in very bad place where they can't seem to push themselves back into the meta, or they tune them correctly and the champion is look passed for other champions in need of balancing

Or The Second in which a Champions Item path is overpowered which ends up in a nerf to the items which effects all champions, or the champion gets nerfed, the item eventually does get changed or nerfed even though it was core to our champions viability and once again... under powered champion

MY IDEA/ARGUMENT:

I think adding bonuses at specific levels to champions that are often problematic to balance could be an actually key component in making them easier to balance and more healthy for the game

For example not saying that it should be done on this champ just how it should work

TEEMO

At Level 4 Blinding Dart recives Blinding effect This in theory would allow room for trades in at early levels If this hurts teemo to much no big deal change the level the effect happens or remove it all together

AGAIN I DO NOT THINK TEEMO IS SOMEONE THAT NEEDS THIS TREATMENT, ITS JUST AN EXAMPLE

Thank You for spending the time out of your amazing days to read this post, if you think this is bad let me know why! If you think this is good say it!