Grenades are pretty useless on heroes.

On TT, one model may use a grenade while everyone else can use their normal weapons.

In Gladius however, everyone must shoot the same weapon so that's why you get a squad of guardsmen lobbing 10 frags like they're Kriegs with a strategem spending CP points. This makes for some dumb moments like all 10 members of a tactical squad spamming melta bombs.

Due to the increased number of models in FoG, you'll almost never throw a single frag grenade as a hero. Kraks are better than their pistols but frags are almost always worse.

I've removed them internally since the abilities clog up the UI and I think that's fine but I wonder if anyone seriously cares about this.

Alternatively we can just give them the grenades as a default weapon and not an ability.

It's technically illegal for them to throw a grenade AND fire a pistol since in 8th, you can either:
Shoot all main ranged weapons OR
Shoot your pistols OR
1 model throws a grenade ONLY.