Well, Passo and Prius/Insight cannot be compared on paper.
If you drive less than 50 kms daily, then maybe spending a lot more money on Prius or Insight is not justified. But if you drive anything in the region of 200 kms and above daily, a Hybrid card will recover its cost a lot quickly as compared to a non-Hybrid car.
And if you buy a genuine low mileage non-tempered Prius second generation, it will give you 21 plus km/l under any circumstances. Insight low mileage non tempered car will stay close to 17 km/l.
So, the choice is clearly yours. Saloon or a hatch back. Whether you drive a lot on a daily basis, or just a few kms to and from work. This would help you decide.