Grenades are...cute. You can generally use them to:
-Charge into melee without striking last. Only thing is most frag/plasma grenade units...really shouldn't be in assault anyway.
-Punk light vehicles that shouldn't be in assault range, or light walkers that shouldn't be used.
-Slow down the game with some extra blast deviations. Or a few blind tests if you like
The current best uses for Grenades are for those units that can:
-Take one or multiple Haywire Grenades. (Solo: Dark Eldar
MSU, multiple: Hawks, Fire Warriors)
-Take multiple Meltabombs. (Tankbustas, Demovets, Fire Dragons).
The former is useful against vehicles alone but has the advantage of working in both phases. The latter against vehicles and monsters, but only in melee.
==Rule Proposals==
Grenades should be useful as a floor for a unit's damage potential, as well as a mitigator against some super-melee. They should also be a relatively fast element to resolve.
=Shooting Phase=
A model in a unit may throw a grenade instead of firing its normal ranged aeapons. For every full five models in the unit beyond the first five, an additional model may throw a grenade instead of firing.
New
USR: Grenadier(X). A unit with the Grenadier
USR may have X additional models throw grenades instead of firing. For every five full models beyond the first five, an additional X models may throw grenades instead.
(Alternately, Grenadier could change it from a "1 in 5" ratio to a "1 in 4, one in 3", etc ratio.)
Blast radius grenades don't scatter. Have fun.
==The Assault Phase==
A model in a unit may substitute all of its close combat attacks to make a single Hammer of Wrath attack using the grenade's stats. If the Grenade had the blast property, it inflicts D3+1 Hammer of Wrath attacks instead. This can be stacked with regular How attacks. For every 5 full models beyond the first 5, an additional model may trade in its close combat attacks for similar Hammer of Wrath attacks. Meltabombs may only be used this way against vehicles, monstrous creatures, and supers.
Grenadier would alter this ratio in similar form and fashion to the shooting attacks.
Units that would potentially have Grenadier:
Swooping Hawks, Wyches, Demolitions Veterans, Ork Stikkbommas (bring them back), Assault Marines, Fire Warriors etc.
Implications: Grenades are less all-or-nothing; units like Fire Dragons get a minor nerfbat in melee, while some like Hawks and Fire Warriors are slightly better at range. Grenades get a new niche as a short-range "reliable" damage channel versus larger units; you don't fluff as many attacks at any rate.
Initial thoughts, as usual, are appreciated.