What do I miss to climb?

I took a look at my (numerous) experiences of this game, and I'm trying to figure out why I can't reach higher divisons.

I know the game, the champs and their abilities, I know the map and its objectives, I can farm properly and help when needed. I know how to be agressive when I'm stronger, passive for not dying, then I can push and roam as the game flows. I can control vision as a jungler or as a laner, wether with wards or abilities (Ashe's E, Akali's or Viktor's W in bush, etc.)

Eventually, my "biggest issue" was team fights: indeed, most of time I play assassins, and I didn't know when to go in, I was like scared. But I solved this problem and now I think I'm okay with this point.

I have a good pool of champions (mostly played: Katarina, Fizz and Akali):

• top: Volibear, Jax, Pantheon, Trundle
• jungle: Pantheon, Jax, Fiddle, Kha'Zix
• mid: Ahri, Katarina, Talon, Fizz, Akali, Morganoob, Viktor
• marksman: Varus, Ashe, Tristanus, Vayne, Ezreal, Miss Boobies, Sivir (and Graves but I hate the rework)
• support: Morganoob, Leonoob, occasionally Pantheon/ Annie/ Ashe/ Fiddle I'm even been playing with a friend for like one or two months, and even when doing "all" right, we can't win. (Well we win some games, but we lose afterwards, so we kind of never climb up)

I have several pages of runes for each of my champions, runes that I customized over time and that I am now satisfied of. Same for masteries.

(please see no offense nor flaming in the following paragraph): During a lot of my games, I'm being matched with people of a clearly lower level of gaming. I can see people unable to farm, stealing experience from Gromp to the jungler cause they "wanted to help", push top lane without any ward, get a Luden's echo or Muramana on Akali cause "it has a lot of AP", and so many other things. Once again no flame here, I'm just seeing. For you to know I'm not a flamer/ afker etc., but I won't hesitate to say a mate when his build is inappropriate (like really inappropriate) or when he's making a bad decision or so. ** TL;DR** **So I'm here today asking for... tips? guides (not lolking guides, I know this haha)? your vision about the main differences between silver and higher divisions? Anything that might help me climbing if I deserve to do so. ** I'd like comments from people higher ranked than me, or people who struggled in low Silver/ Bronze.

P.s.: don't judge me according to my recent history, you should know that even when you're doing good as an ADC, if a fed, mid laner assassin jumps on you, you're dead, or when you're Katarina vs Riven it's hard to farm, etc. Everything happens in this game.

Thanks for those who will read this and answer me.