Step one
Find an exotic that takes skill or is fun to use. Like you say everyone is using thorn, shotgun combo. Look for something fun not a crutch. I use plan c a really fun gun to use as it matches my playstyle.
Step two
Find a game mode. You can't change the map, [b]yet[/b]. But you can change the game mode. Here are my top three(combined arms, control, clash.)
Step three
Find out your play style and use it. Use it with exotics, and legendaries. For armor find a good perks on legendary. And one good perk for exotics. For guns use the same on your favorite gun types