Honestly, the shrapnel was great for add-clear because of its huge splash radius, which made it great at keeping your teammates safe during enemy reinforcement events from a safe distance. It was much more useful at cleaning up small enemies than it is currently at medium enemies, and doesn't really handle either one that effectively anymore. I feel like it doesn't really feel like an appropriate pick for any role right now.
Still good for dealing with nests and fabricators from afar, but we're starting to get a lot more options for this lately, as well.
I think like the railgun, the eruptor was just too strong for its own good, at a conceptual level. I mean, "sniper rifle/grenade launcher that you spawn in with for free" is kinda OP.
I still like playing at range, though, so I might give the marksman rifles another try now that the sights are fixed.