The problem is our gear "upgrades" at this point DECREASE our DPS.....
The excuse is always gear isn't it... Try playing better, that is the best solution. You may think that there is "nothing else you can do but get more gear," but that is NOT true 99% of the time. Maybe some of your DPS aren't using optimal builds, or they don't have optimal stat setups. Maybe some of your DPS suffer from latency. Maybe some of your DPS just simply didn't play that well on that particular attempt. There are a number of things that could have held you back.
When you really know how to play your class what it really comes down to is uptime
. This means reducing the amount of time that you aren't DPSing as much as possible with out dying or taking unnecessary damage. Good positioning can help reduce the amount of times you will need to move, standing too close to others could cause you to have to move out of someone else's AoE for example. Don't move more than you need to, don't move 20 yrds when targeted by a 10 yrd AoE, move 11-13. DPS while moving, as a lightning sorcerer I can shock when ever I'm moving, and if I'm still moving after that I could even clip affliction. Just little things like that go a very long way.
You also seem to be unaware that you can use different mods and enhancements. Even in rakata and columi there are mods that have less endurance more dps stats, and some have more endurance less dps stats. You want to buy multiple pieces of gear so you can swap the mods around for optimal stats. Stack all mods with high DPS stats less endurance, and use properly itemized enhancements.