Plants are just a band-aid solution to a larger problem.

League needs more micro opportunities rather than macro opportunities so the game can't just be mathed out.

Look at StarCraft. You can "solve" the game all you want, but the skill and variance comes from a player's micro - how they EXECUTE a build, how they PERFORM on a certain race.

Allow players to adopt unique playstyles with the same champion by diversifying itemization, jungle routes and even ABILITY builds.

Nearly every champion has a set-in-stone "Max this skill first, max this skill last.", **and that's just poor game design. **

Dare I say it, DOTA is pretty amazing when it comes to providing multiple ways to level up a hero (champion), build a hero and play a hero. League of Legends severely lacks in having DIFFERENT ways to play a single champion.

Admittedly, Riven is a decent example of a champion that has many builds and playstyles that has a purpose for different situations.