I play my 80 engineer now and then, and like my build, but grenades are going to give me carpal tunnel and RSD. I have brought this up to Anet before, as it is somewhat of a serious matter.
My idea to fix grenades so users dont hurt themselves is this:
Make grenades likes homing shells from Mario Kart. This way they still hit a target if it blocks LOS (like current nades) and allows players to evade them etc (like current nades). They could even look like those little wind up bombs with feet.
It also seems odd that the mine kit does not have anything special to it, while the bomb kit has many different attacks. Maybe combine these so bombs are more like mines (explode when someone is near), but have the same attacks as bombs do now.