Stuck in Bronze Any Suggestions

I've worked on everything everyone has told me. Specialize one champ, work on pinging, don't let yourself get tilted (no one is perfect on that), main in a role that you can carry easily (ie bot,mid,top, jg) [was already mid main anyway]. There were a lot more suggestions that I have also worked on, but do not rant about that. Still I find myself to be struggling to win promotion games because of teams that are just beyond helping. Even during those games of course I will continue to try my best to recover against a fed team. Most of the time it seems pointless to continue playing in the elo I am in because I don't feel im progressing skill wise. Generally the only way to get better at something with opponents is to challenge yourself. The only challenge i receive in this elo is against opponents who are fed. While its good to know how to play against a fed opponents, as its something that will happen in all elos of course, I am not getting any better at dealing with opponents who just feed me and don't really teach me any of my errors by out playing me.

Lastly, one thing I've noticed is that my win rate% has been very high this week as I have spent A LOT of time playing. Not to say all of my games were great, because not all were. However I have a lot of objectives taken (or assisted in taking) and a very high avg kill rate. (as a mid assassin) Low deaths, so on so forth. However I am not noticing any difference in rising in elo beyond what I have already risen to in the past, (bronze 2).

Any more suggestions I never mentioned that don't require starting over with a new champion? Or am I really that hopeless in regards to getting to silver 5?