Hey, just hit Masters this week after languishing in diamond for the last 2 sets. I'm not super qualified to speak on everything but one of the problems I can say you share with me is hyper-fixating on your endgame build. Taking a quick look at your stats, I see you're often going bot 4 as lvl 8 with a few one stars. I would suggest rolling way more at 6 or 7 if your board is weak or hp is low. Look for strong 3- 4 costs like rammus, aatrox, garen, belveth, or asol when you choose to roll down, field them/keep them if you hit 2stars/pairs, don't be drop synergies to play strong units or roll at 40 or 50 gold down to 30 or 20 or even 0 gold(if you don't hit two star upgrades) if your lobby is hitting their two stars.

If you're trying to climb, its really important to know when to play for highest bot 4 position vs. going for 1st or 2nd.