Well i can see this list being in the face of the enemy by the end of turn one 

 but anway,  the lootas i'd consider splitting them into two groups  one with 7 one 8 (so they can still go to ground) as lootas are like otherboyz with the mobrole and fearless units can not go to ground :/ Taking buzsaws your best shot would be having the  deffkoptas in reserve and outflank your enemey.. using the scout rule in sixth makes you unavaible to charge the same round :/ but i would skip the grot riggers it wont be avaible to move the turn it's being used  and you got a big mek innside it to repair either weapons or hullpoints anyway 

 that goes for trukks aswell only thing worth for them is ramshackle you get to reroll dangerous terrain aaaaaaaaaaand you get the KAREEEEEEEEEEEEEEEEEEEM rule wich might end up if your trukk explodes it might deny it! (oh and bonus)  if it does... you will only take 
str 3 hits instead 4 like the other codexes does 
 
 
 Edit: i would also consider reading the terms of posting lists (adding points every single thing is not allowed)