I'm plateauing in Crucible where I can outshoot most people but I put myself in awful situations and get killed. Any recommendations where to start improving?

I play a ton of Trials (~1650 elo 1.4 kd on my hunter) but I run across teams who just out-position me far too often. I snipe and hit my shots but I put myself in bad places and get frustrating deaths : ( I figure I should start studying heat maps as a starting point. Are there some good ones, or good advice otherwise, that you can point me to? Thanks guys.

edit - thank you for all the advice so far. I really like what I've heard so far and I'm planning on recording my gameplay on twitch more often so I can critique and learn from it