Yeah, LB's in general just are in a particularly rough spot.
It's basically a binary option of either it's 100% useless or 100% useful (In the case of Tank/Healer LB's)
Then outside of that it's basically mDPS LB's > rDPS LB's because most of the time you're wanting to LB a boss, in which case the higher damage ST ones from mDPS are better.
Making LB's individual, while not only causing a huge balance issue (Since, either every class would be designed with completely unique L1/2/3 LB's and balanced around how quickly they generated LB's) or it would change very little as Tank/Healer LB's would still be binary useless/useful. The major thing would be pushing more mDPS to be in parties for multiple ST burst LB's.
Honestly, if they want to make all LB's useful, without just slapping in mechanics that force specific ones to be used or its a wipe, would be to enhance the less desired LB's in some way.
An example could be directly buffing some LB effects. Such as making damage mitigated/healed by Tank/Healer LB's give a proportionate damage boost. Or making rDPS LB's debuff the enemy increasing damage taken.
Or an alternative could be something like being able to Combo LB's. Taking inspiration from Ungarmax (The Squadron LB where all 4 members channel together for DD and a damage boost). What if instead of LB's being a one shot of a single person gets to use a LB and that's it, what if classes from other roles could, after that one person has started their LB, could ALSO LB to create new effects?
Such that you could end up comboing in different ways for different effects. Such as DPS > Healer > Tank would produce a different outcome to Tank > DPS > Healer.
Which, yes, would require a lot of balancing to incorporate, but once done would mean that all roles would have viability to use LB's without situations like currently where they are either pointless or absolutely needed, if of course the effects ended up balancing out each of the 3 DPS types (mDPS/rDPS/magDPS) so that mDPS wasn't always the superior one for bosses.