As others have said - what constitute offmeta is quite a wide spread, and you can clear everything without a single build that is exactly as SC/LN/etc prescribe in the squad. Bringing suitable boons is important for DPS, try hitting the golem with your DPS rotation with and without boons, they make up for around 2/3rds of your potential damage (assuming your class does not generate many). However, if you are pugging raids with very offmeta builds, please ensure that you can fulfill the role you sign up for - sign up as DPS, be on par with the other DPS or at least above the BS. sign up as a quickness provider, provide enough quickness while dealing reasonable damage, etc. Some of the reasons why the meta builds exist are squad synergy, and unique buffs - for example tempest or renegade can out heal a druid at every encounter, however you don't have access to spirits, or the very fast 10 player might stacking that druid brings.