QUOTE
grenade: inf terr
flare: medic+flare
mine: spider mine
napalm grenade: firebat
bio grenade: defiler+plague
sentry: lurker(?)
well as for the inf terran thing, its a bit... stale and overused, you can try adding some originality to it by, making a 3x3 and a 4x4 location center in a remote spot, then by using switches, whenever an inf terran comes up make the locations focus on it, then if an enemy comes to the 3x3 area spawn air units (Ones with cool looking deaths) and blow up all units (uncluding inf terran with death trigger), deactivate the switch so the locations go back and preserve the trigger, and your set!
As for a mine, believe it or not you can use an inf terran also
make the 3x3 location a 1x1 and the 4x4 a 3x3,when an enemy comes to the one by one location (which is impossible when its above ground so you'll have to burrow to simulate a mine!

) make a 3x3 explosion with units and your set

as for any suggestions, I think you should have a suicide bomber thing

but thats probably not gonna happen.