...how would the car list go? Here's my opinion:
Sakura Aquila City and Forte: Proton Wira or Mitsubishi Lancer
Sakura Aquila Metro ST: Mitsubishi Lancer Evolution V
Sakura Aquila Space: Proton Satria
Dalton N90: Despite being based off the Dodge M80, I would suggest a Mitsubishi L200 pickup truck. You see, Mitsubishi and Chrysler had a joint venture.
Garret Traver-Z: Ford Mustang GT (2005 model), because the Ford GT is too fast and the Ford GT90 is a concept car.
Poloma Renegade: Chevrolet El Camino
Boyd Fireflame 544: The Holden Efijy is a concept car, so let's go with a grey import Chevrolet SSR instead.
Chevalier lineup: Since Chevalier sounds Chevrolet, I would suggest an Isuzu D-Max pickup truck.
Vaultier Patrolman: I don't remember compact coupe utilities being sold in Southeast Asia, but I would suggest a Chevrolet Montana imported from Brazil.
Titus ZJ: Something like a TVR would be good enough.
Civadier 999: Looks like a Kia KCV-III concept. I don't like concept cars being seen on the road. The sportiest Korean car would be the Proto Motors Spirra, so let's go with that.
Additional cars: Toyota Fortuner (spawn in the Lautan Lama Desert), Proton Gen-2 (spawn in Panau City and west Berawan Besar), Toyota Caldina (popular grey import like in Malaysia, should spawn in Panau City), Toyota Hilux (spawn in the Lautan Lama Desert), Perodua Myvi (spawn in Panau City) and 2006 Asian Toyota Camry (spawn in Panau City).