In Promos to Reach Silver, Need General Advice (This is Long and Detailed, Brace Yourself)

• Lost the first two matches being Vi in the jg. General consensus seems to be that I was okay and at least some people were utter apesh**, but I tend to beat myself up instead, thinking of how I could have overcome that to get the win.
• Feeling that I do not know how to pressure a game (apart from playing ), or carry a game from behind; my playstyle is trying to be safe, avoiding situations where I would die and feed gold even if it means giving up objectives; also making picks as a jg or engaging/peeling as a support. Come to think of it, I exacerbated issues in the lost games by trying to blow up the squishies or low-health people in 1v4 situations (poor decision-making on my part). I do well when my team does well, and I go along for the ride, making picks when I can, but I don't consider myself to be very good at early ganking, though IDK if that's the self-defeatist tilt speaking or the actual skill I have at ganking. TL,DR: I don't like risks.
• My main champions currently (that I know I do well somewhat consistently on these days): . I have no idea how to find out what position I can consider my main; jg was something I mained at first, but then Vi's ban rate skyrocketed. Then I was top, but a losing streak on Sion soured my confidence in it. For top I currently stick to or , but a number of my losses have been for when I couldn't play as my mains and went with champs that I had winning streaks with in the past (, , ), only to suffer badly enough to lose my faith in carrying with them. That said, I need a way to find my comfort zone that I can start finding champions for (what position to main, which champs I can do well with in a passive opportunistic sense, which champs can be used in multiple areas without drastic changes to their playstyles, etc)
• Also told that I am a REALLY sore loser, the kind whose mood deflates exponentially when I lose playing someone that I like the character of on whom I tried to do cool things with or play well really hard. Hates being told that my best isn't good enough, even if I acknowledge that to be true. Wants help but doesn't want to go through someone else's rigid teaching structure; wants to win learning and working on things alone or with friends, not as a student for some Diamond main. Wants LoL to remain a game, despite the stress of ranked, not a job or class outside my own choosing. Contradictory, but then again that's mild Asperger's for ya: rigid mindsets with slow pace of thought everywhere. I also prefer playing the game itself over chain-watching/taking notes on streams. ALL OF THIS IS SUBJECT TO MY DISCRETION, mind. Mine's just not something I feel confident in at the moment.

I could still use an outside opinion or few to help me see the direction I should be headed now to keep climbing: HELPFUL opinions, not rants about how everything I worked on is terrible and that I should uninstall or stick to Normals without screwing everyone else over. Also aware that "there may not be enough data to give a complete picture of my situation"; LoLKing, op.gg, and Match History profiles are the best I have.