Inconsistent compared to what?
Which other weapon upgrade requires you to manually shoot it?
Inconsistent with every other infantry weapon in the game that I can think of... They all auto-fire to my knowledge. That's the point I'm making.
I'd prefer the RE grenades be an auto-fire weapon along with every other weapon, but an AOE weapon that has to be dodged, while also requiring no input to fire them is a bad idea despite me liking the RE grenades in principle.