"I have a 10M roster and barely get 700k in raid"
Skill issue.
"there is just not enough choice of toons that can be used"
...because that's how I feel (translation: I should be allowed to use the GL I've had for 3 years in the raid so I can crank out a high score without a single thought or bit of effort)
"I can’t just gear up toons I have no expectations of using unless they go towards GLs or Legendarys"
DS Clones, TG, Depa -> required for JMMW
Pirate marquees -> required for GL Hondo
There are also Era Battles, conquest feats, datacrons, and just the most obvious fact that new stuff tends to be the power creep that comes to dominate the meta. But suuuuuuuuure... there's no expectation of using the new characters. None at all. It's not like they have a raid or a legendary or a GL or anything.
"and to fill it out with new marquees is rubbish"
There's a team that can max score on the highest difficulty tier that doesn't require a single one of the new marqees: KB, Jocasta + pick any combination of old JV (like Shaak or Aayla). So, at the very least, with this single team, you could be scoring 3.6mln in the raid with one team, with none of the new marquees (compared to the 700k you're scoring now).