Brother, According to my information (may be I am wrong), 185/65/R15 might harm your suspension as it's overall diameter is 24.47. Do not put bigger diameter than "With stock suspension, you may safely fit many tyres from 23.0 to 24.3, +/-3%".
You can take 185/60 R15 which will look really cool. Toyota has offered this size in it's stock. But it will not give you a good ground clearance as it's overall diameter is 23.7 only. The 195/60 R15 has total diameter of 24.2 which will give u a great height with in limits. If you do not like "195" width then go for "185/70 R14" which has overall diameter of 24.2. But 185/65/R14 has diameter of 24.47 which is a way bigger than stocks.
Please do not exceed overall diameter limit of 24.3 as it's not good for suspension. For details check this link:
Official YARIS Wheel & Tire Guide - Toyota Yaris Forums - Ultimate Yaris Enthusiast Site
Check this: This ride is with stock rims of 185/60 R15 and this size looks the most beautiful in vitz:

below is the ride of doc Junaid bhai with 195/60 R15 they look cool too.

This is 195/60 R15 from michelen. Feels awesome!
The last picture attached is the mortal bhai's 185/70/R14.
Bro. plz update me if you find any thing wrong in my research.
Best of luck!
