CG Can we please lose the 600 raid cap

If they increase the cap, guilds will still demand max tickets a day, because that would bring the chance to do more raids a week. It wouldn't solve op's problem. On the contrary, for some players it would be more difficult, and the feeling of "carrying dead weight" would be even bigger for them.
Possible solutions: be patient and accept that some people value life over games, try to convince slackers to be more serious, make your officers be more exigent with slackers, leave for a more exigent guild...