need some zdoom scripting advice

I'm trying to modify this amazing wad which was reviewed in newstuff # 413 where the over-poweredness of the friendly A.I was, quite rightly, criticised. I've never touched zdoom scripting, but I believe I have a motivation to do so now. Going by what I've pasted below (a very small part of the decorate script) I'm guessing that the normal player health is 100? And the higher the pain chance value is to, well, increase pain chance rather than decrease it? Also, if anyone has any tips on making the gameplay more balanced, then please do let me know.

//*****************************************************
// Friend:usmc
//*****************************************************

ACTOR US_Cap : biafriends
{
Health 1900
Radius 10
Height 56
Speed 20
PainChance 2
MaxStepHeight 32
MaxDropoffHeight 32
MONSTER
DONTHURTSHOOTER
+LOOKALLAROUND
+FRIENDLY
+FLOORCLIP
+PUSHABLE
+NOBLOCKMONST
+NOTARGET
+QUICKTORETALIATE
+DONTSPLASH
+DONTBLAST
+FIXMAPTHINGPOS
+NORADIUSDMG
+SLIDESONWALLS
+FORCEXYBILLBOARD
+ACTIVATEIMPACT
+DONTHURTSPECIES
+MISSILEMORE
+CANUSEWALLS
+NOVERTICALMELEERANGE
seesound "USC/sight"
AttackSound "MP5/shot"
painsound "USC/pain"
deathsound "USC/die"
activesound "USC/sight"
dropitem "FMP5" 256
dropitem "dogtag1" 256
States
{
Spawn:
DPOS AB 10 A_Look
Goto See
See:
DPOS AABBCCDD 3 A_Chase
DPOS A 0 A_Jump(6,"giveammo")
TNT1 A 0 A_Jump(64,"ClearTarget")
Loop
ClearTarget:
TNT1 A 0 A_ClearTarget
Goto See
giveammo:
DPOS A 0 A_CustomMissile ("ammobag_us", 40, 30, 20, 2, 3)
Goto See
Missile:
DPOS E 1 A_FaceTarget
TNT1 A 0 A_CustomMissile ("gunlaser", 30, 0, 0, 2, 3)
DPOS E 0 A_Jump(8,"snipe")
TNT1 E 0 A_custommissile("bia_gunflash",30,0)
DPOS F 2 Bright A_CustomBulletAttack (2, 2, 1, 6, "BulletPuff")
TNT1 A 0 A_CustomMissile ("gunlaser", 30, 0, 0, 2, 3)
TNT1 A 0 A_SpawnItem ("CaseSpawn_P", 0, 30,0)
DPOS E 1 A_CPosRefire
TNT1 A 0 A_CustomMissile ("gunlaser", 30, 0, 0, 2, 3)
Goto Missile+1
snipe:
TNT1 A 0 A_CustomMissile ("gunlaser", 30, 0, 0, 2, 3)
DPOS E 10 A_FaceTarget
TNT1 A 0 A_CustomMissile ("gunlaser", 30, 0, 0, 2, 3)
DPOS E 0 A_PlaySound("MP5/shot")
TNT1 E 0 A_custommissile("bia_gunflash",30,0)
DPOS F 1 Bright A_VileAttack("snipe/shot", 20, 15, 3)
TNT1 A 0 A_SpawnItem ("CaseSpawn_P", 0, 30,0)
DPOS E 5 A_CPosRefire
TNT1 A 0 A_CustomMissile ("gunlaser", 30, 0, 0, 2, 3)
Goto Missile+1
Pain:
DPOS G 4
DPOS G 4 A_Pain
Goto See
Death:
DPOS H 8
APOS I 7 A_Scream
APOS J 7 A_Fall
APOS K 7
APOS L -1
Stop
}
}

You can find explanations of pretty much everything in that code on the ZDoom wiki; mostly from these three pages:
http://zdoom.org/wiki/Action_functions
http://zdoom.org/wiki/Actor_flags
http://zdoom.org/wiki/Actor_properties