>>717262469 (OP)LBG's main strength lies mostly in utility and customization - as in each LBG is vastly different from another one due to different ammo types in different quantities with different reloads and mobility etc. that you can mod further slightly, and it really affects gameplay while most other weapons don't have much of a difference it terms of gameplay itself.
With utility it's healing others, buffing them, putting shit to sleep, paralyzing, etc. you're basically a walking status dispenser on demand and that's basically the most useful LBG is ever gonna be.
You can also go with an LBG focused on singular ammo type, while it's not as useful it can fulfill your niche power fantasy if you want to feel like you have a grenade launcher, sniper, shotgun etc.
You can also take shit in-between obviously, as I said LBG allows for a lot of variety in its own class. Though going for one ammo type focus LBG isn't as good as just taking other weapon types in terms of damage.
That said, speaking about World, personally ever since the Stygian Zinogre released whenever I play LBG I just use his.
Spread 3 with good mobility (and basically nothing else) is really fun, having to stay up close and blasting monsters in the face with your mega shotgun while dodging whatever they do is some great stuff.