battlefield Birmingham 5 40k tournament

[Cookie101]

you realise the 'ard boys are troops right, they are an upgrade of regular boys

If I turn the 'ard boys into shoota boys that gives me 80 points to play with which is 2 units of minimum sized grots (aka 10 grots and a slaver), which bumps me up to 5 troop choices (the mega nobs, 2 shoota boy mobs and 2 grot mobs) if I did do that I would drop the nob form the unit and get 2 big shoota in each of the shoota mobs, which leaves me with 20 points to spend.

so the list would be:
orks (1850)

warboss - mega armour, cybork body, bosspole, attack squig. pts = 130
big mek - heavy armour, kustom force field. pts = 90
6 mega nobs. pts = 240
battle wagon - 3 big shootas, grot riggers, deff rolla, red paint job, armour plates. pts = 145 (transport)

20 shoota boys - 2 big shootas. pts = 130
battle wagon - 3 big shootas, grot riggers, deff rolla, red paint job, armour plates. pts = 145

20 shoota boys - 2 big shootas. pts = 130
battle wagon - 3 big shootas, grot riggers, deff rolla, red paint job. pts = 135

10 grots + slaver. pts = 40
10 grots + slaver. pts = 40

5 burna boys - 3 meks. pts = 75
lifta wagon - 2 big shootas, grot riggers, armour plates. pts = 250

15 lootas. pts = 225
sky shield. pts = 75

20 points left over.

would this list be better? I spent the 20 points on some armour plates for 2 of the battle wagons, is this worth it?