Maul was released via conquest for LV the same way Cat was released for JMK. Both are much weaker without those lifters. Doesn't matter what you say about it or that Maul makes no sense as LV's lifter. The fact that people often split Maul and Bane off into their own thing doesn't mean they weren't the intended lifters.
JML already has two effective lifters, JKL & Jedi Cal.
As your roster gets bigger, you have more options for squads than you have opportunities to use them. You start combining these characters into very, very strong squads, like JML, JKL, Jedi Cal, Revan. All of who could be leading their own squads.
Leia and Jabba don't have designated lifters, yet, because they haven't really been power crept the way SLKR & Rey were by subsequent GLs. When there's a problem they'll sell you a solution. Endor Luke, with a rebel tag. Jabba has the possibility of getting another tank, so Krrsantan can be spun off to go with Aphra.