Reliability versus Potential
Champion diversity consists of a lot of things, but one factor I've almost never seen discussed in reliability and potential.
So what is reliability? Well, what I would consider a reliable champion has:
- Clearly defined in-game role and objective.
- Somewhat predictable gameplay, but not "bad" gameplay.
- Straightforward abilities.
What are some reliable champions? Well, for example (in my opinion):

On the flipside, there are champions with potential. Champions with potential have:
- Flexibility with their playstyle.
- Unpredictable but easily interrupted gameplay.
- Many options in terms of what to use their abilities for.
Some champions that have a lot of potential (in my opinion):

Some of you might be thinking:
"Oh, so reliable champions are noob champions and champions with potential are good ones?"
But this way of thinking is flawed.~~ Balancing issues aside~~, both these types of champions have merits. I wouldn't really consider any of these more "pro" than the others, although reliable champions are technically "easier" to play. That's exactly it though:
**There is a clear tradeoff between these two types of champions. You have to ask yourself, "Do I feel confident enough to potentially do really well?" or "Do I want to add more reliability to my team and have more streamlined gameplay?" **
These two types of champions have to exist, because they complement each other. If only one kind of these existed, the game would either be too boring or too tedious. They balance each other out, in a way.
With reliability you can beat somone with potential through sheer simplicity. However, someone with potential can predict your movements easily and beat you that way. Both of you will have to adjust to this and whoever can do it best will win, requiring skill from both of these types of players.
What do you guys think? What kind of champions do you prefer? (poll)
Thoughts on this?