Before you start judging a champion, understand trade-offs.

Please take into account EVERYTHING in that champion's kit.

Here are some thing you need to review before criticizing a champion.

1. Range. This is the reason Cho'gath has a fuckton of damage and a true damage ult, while Ziggs has only meh scaling and damage on his kit. One is more reliable and less prone to kiting, the other is ungodly powerful.

2. Passive. Often underrated, this can add a huge amount of power or utility to a champion. Katarina is a pretty pathetic duelist unless she's fed, but her she completely revolves around her passive allowing her to pentakill in teamfights. Rumble's passive allows his kit to be balanced while being resourceless, giving him a small buff while in danger zone but punishing unwise decisions and spamming abilities.

3. Base stats. Possibly even more underrated than the passive. Look at Akali who who has fairly modest AP scaling and only 3 attacking abilities. She has quite high AD, AR, AS, and even more MR than Shen, with an amazing MS of 350. Her passive only makes her raw stats even higher. On the other hand, Anivia has fantastic AP scaling and a good bit of utility, but the lowest hp of any champion in the game.

4. Mana costs and cooldowns. Malzahar begins with 9 14 15 second cooldowns on his 3 basic abilities, costing 80, 90, and 60 mana with that cost going up each rank you put into it. With that in mind, he also gets a 1.4 to 3 second silence, max health% damage, and a targeted DoT nuke, all of which have incredible AP ratios. This makes him one of the strongest mage duelists in the game but also gives him huge windows of vulnerability.

5. Early game vs late game viability. Pantheon and garen for example have very strong laning phase potential but fall off the longer the game lasts. Conversely, Nasus has the weakest early game of any fighter and possibly any champion in the game, and Vladamir is powerless to an all in vs many early game champions, but both are capable of dealing respectable damage while taking very little in return come late game. This tradeoff makes these champions balanced.

6. Teamfighting. Galio, Amumu, Sejuani, and Leona are pitiful duelists, but they are all top 10 highest winrates in the game because their ultimates carry in this teamfighting dominated metagame. On the other hand Udyr is one of the strongest duelists in the game with pitiful teamfighting.

7. Utility. Someone like Janna brings almost non existent damage to the fight, but has a lengthy knockup, enormous shield + AD buff, slow, and knockback/heal, giving her the most utility of any support. Sona is quite different. Although she has several utility abilities and several more utility options with her passive, her utility is very weak without her ultimate. Instead she brings quite a lot of reliable damage to bot lane.

8. Power buttons and lopsided or clunky kits. Raw damage and scaling is not always a good indicator of the actual damage you will deal in a fight. Karma for example has a spammable Q (her power button) that turns immensely powerful when combined with mantra, but that uses up her ultimate and leaves her with an unreliable and dangerous tether that forces a squishy mage to stay as close to an enemy as possible, and a shield without damage. It balances her poke with her all in damage quite nicely, especially after the adjustments she received in 5.10. Now take a look at Nidalee. Again she has a power button in her spear, her traps do practically nothing, but she has utility in her heal and added burst in her cougar form. She's annoying to lane against but I would consider her damage to be balanced.

9. Reliability. Morgana has a 3 second root that travels at one of the lowest missile speeds in the game and can't go through minions. It has fantastic base damage and AP scaling on a medium cooldown with long range. This awards intelligent players who save it for the best time rather than trying to blast someone the moment they think they might have a chance to hit someone, while adding a lot of counterplay to it. Taric's dazzle is a measly 1.2-1.6 stun on a long cooldown with abysmal scaling and short-medium range, however, it cannot miss. This is where counterpicking comes in handy. You wouldn't want to pick a Morgana into an Ezreal because your chances of hitting him are very low. Instead, Taric's guaranteed to hit ability may help you win the trade.

Now let's take what we've learned from the above and use it to assess a champion. I've seen a lot of threads going around about Lux's mana cost on her E being too high.

1. Range. Lux has enormous range on all of her offensive abilities.

2. Passive. Her modest AP ratios are offset by her incredibly powerful passive, adding 400+ base damage and 60% ap scaling if used with her 3 damaging abilities.

3. Lux's base stats aren't really shockingly bad or good. She has 330 MS which is to be expected with a mage with such huge range and CC.

4. Mana costs and cooldowns. Her ultimate is 100 mana which is quite standard for ultimates but it has an extremely low cooldown. Her Q and W are low-medium cost with medium/long cooldowns. Her E is what most people want changed, at a 70-130 cost and medium cooldown, but review all of my main points before agreeing or disagreeing with that notion.

5. Early game/Late game. She's pretty balanced in this regard. She has fantastically strong waveclear and poke in her E which gives her a reliable laning phase and her utility + long range ensures she remains useful lategame.

6. Teamfighting. 2 forms of CC, a very strong aoe shield, aoe damage, and a massive aoe nuke. Some champions are better in this regard but I would consider her to be very capable in a teamfight.

7. Utility. Again, 2 forms of CC and a shield. You may also consider her ultimate to be somewhat of a utility because you are able to snipe an enemy with it.

8. Power buttons/lop sided kit. Points 8 and 9 are easily the best ways to explain the mana cost of her E. Her Q brings great utility with fair damage on a long cooldown, and her W is a strong shield. Nothing fantastic yet. Now her E is her power button. It functions as waveclear, sets her passive up to proc on multiple enemies, slows, and gives vision on a medium cooldown. I would also consider her ultimate to be disproportionately powerful in her kit.

9. Reliability. By far the biggest reason Lux's E is so strong and probably warrants the high mana cost. It has a lightning fast missile speed, enormous radius and little or no cast time, making it one of the most reliable and difficult to dodge abilities in the game. Compare hitting 100% of Lux's Es with hitting 50% of Ziggs's Qs and the mana costs are almost identical.

Overall I'd say Lux is fairly balanced and healthy. Lowering the mana cost on her E would buff her very strong and reliable power button and allow her to farm with no risk and force enemies out of the lane with no counterplay. The high mana cost is the only thing keeping Lux from being unstoppable in the laning phase.

If you'd like to add anything to my list or offer feedback feel free to. I made this with the intention of providing insight and clarity, not to defend or attack champions.