Which position is the most important and why?

Shopkeeper

Doggy style.

All of them.

There's no one answer to this question because it depends on what aspect of the game you consider to have the most impact on victory. An argument could be made for each position and each class of champion.

mid and jungle generally have the largest impact on the game.

then bot lane.

then top lane.

front

For me: Mid = easiest lane to carry the game with Support = when I want to have fun n pick random champions/builds

Honestly in my opinion Mid is. now here is my explanation before all the ADCS and tanks and junglers jump me, hear me out!

It is the mid champions job to push the enemy tower down ASAP! And gank other lanes that the jungler is not able to get to.

ONCE the mid enemy tower is down, you push the lane more to where your minions are pushing up against their next tower...then you go bot and help bot push their tower in the best you can. once you "unlock" your bot they can roam mid and push the next mid tower, then go top and "unlock" top...Tower priority should be Mid>Bot>Mid>top>Mid(Inhibitor if possible) then baron it.

This line of discussion makes so many assumptions though. If all other factors are equal then any position can be THE position as long as the individual player is better than their opposite number. Also, there are specific champs you can use designed to "carry" in almost any position (YES, even in support). What really changes is the definition of "carry" depending on the position.

Depends on the Elo.

In Bronze and Silver it is the mid lane and jungle.

The bot lane doesn't matter too much since most ADCs have poor positioning and just get deleted in fights even if they are fed.

I think the Top lane doesn't matter too much in silver and bronze.

In higher Elo, I think the other positions balance or even out, with probably the jungler having the most map impact in Gold.

I am a mid main, and objectively, I would say jungle is (generally) the most impactful role. I've seen a great jungler carry more often than any other role, and not because they do the most damage, but because they can get every other lane fed. On the flip side, a terrible jungler can quite as easily cost you the game.

I think its Mid and Support,

Mid is where you usually get most fights + 1v1s. Which means its the lane that can get out of control really fast. That's why most junglers and supports love to play around mid and roam when ever they can (example Hylissang roam mid constantly for Fnatic). Plus having mid control and taking first mid turret provide you easy access to enemy jungle and open the map for your team to play around. It also enable your top and bot to play aggressive. Plus you can also roam and impact the game in your team's favor.

Support is also very important. Support is what most comps are based on. Having hard engage or peeling support create unique comps and play styles. Support normally dictates warding, keeping an eye on the map, shot calls so on. Plus lots of support picks are based on counters. Ex picking morgana in to blitz or thresh. If you snow ball hard from those counters u can win bot easily. which means you and your adc both are up in gold and xp.

But "most important lane" depends on patch and meta changes. so its better to keep an eye on all the changes around summoners rift =)