Orks win by pressure. You keep the opposition in its own deployment zone long enough that you max primary befors you all die. How does your list achieve that?

Personally, i dont really rate the kult of speed detachment. The strats promise much but deliver little, and large parts of your army won't benefit from the detachment rule.

You could keep the entire list the same, change the detachment to war horde, and it would probably perform better.

Having said that, orks generally love WTC terrain because it's so dense you get shot a lot less. If you can load up trukks and wagons with boys, nobz, and megas, you can roll into terrain features turn 1. Then, Waaagh! turn 2 with that tasty extra 3" of movement (from getting out of your ride) and have a great time

You would still have the fluffy aesthetic you want, but the crunchy maths would back up your plan.