I feel stuck...

Hello everyone. Iv'e been holding off ranked for sometime now just because I'm not very fond of the toxic mindset that ranked produces. Not in me, but my teammates. I'm a very calm player and I don't flame if someone feeds or doesn't do exactly what they're supposed to. I'm also a very positive player and I try to raise my teammates morale in despite of things going sour. "Good job", "Nice dodge", "We got this, don't give up yet!", etc. However I feel very stuck in my MMR/Elo. I usually have low deaths, try to handle objectives the best I can, and overall try not to feed. I'm more a reactive player than aggressive. I just feel like my skill level is a little higher than my elo and I'm not sure how to go about getting out of it. I'm very aware this is a team game and a lot of people don't see that, they think if they're fed they can do dumb things and just throw their presence out the window lol. People in my elo usually do the same mistakes over and over again and then if you try to give them advice they're just so immature about it. :( So do you guys have any tips for me to raise my mmr/elo? Sorry if this was a little ranty, I'm just starting to feel like I'm stuck haha.

Background:

I was S3 last season and towards then end I fluctuated between s3-s1 never getting to gold because of the reasons stated above. That's not to say every game was my teams fault, I have faults as well just not as frequent. I also try and take roles if my teammates aren't comfortable with the certain role they were forced into as I am comfortable with just about all the roles.